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How much oil do you use? (4 stroke)
Guys,
I am trying to find out how much more (or less) oil a 2 stroke uses compared to a 4 stroke. Thus, I need to know about your 4 stroke motor (inboard or outboard): - Horsepower, brand - amount of oil it takes for an oil change (incl filter) - how often do you change your oil (how many hours) - how often does the manufacturer recommend you change the oil? - Does your motor burn or lose oil? Do you have to top up in between oil changes? Thanks for your help! Matt |
I have a 4 stroke merc 60, uses no oil between changes @ 100 hrs.
Be sure to tilt motor all the way up and then back down before you check it or change it so you drain out all the nooks and crannies. |
"Matt Lang" wrote in message om... Guys, I am trying to find out how much more (or less) oil a 2 stroke uses compared to a 4 stroke. Thus, I need to know about your 4 stroke motor (inboard or outboard): - Horsepower, brand - amount of oil it takes for an oil change (incl filter) - how often do you change your oil (how many hours) - how often does the manufacturer recommend you change the oil? - Does your motor burn or lose oil? Do you have to top up in between oil changes? Thanks for your help! Matt Don't have specs in front of me, so I can only answer the last question regarding my Johnson 1996 15 hp 4 stroke (model J15FREDR). It consumes NO oil between April and November. Zero. I change it twice during that time period, and based on memory, that's about twice as often as OMC recommends. |
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Matt Lang wrote:
Guys, I am trying to find out how much more (or less) oil a 2 stroke uses compared to a 4 stroke. Thus, I need to know about your 4 stroke motor (inboard or outboard): - Horsepower, brand 80/na - amount of oil it takes for an oil change (incl filter) 6 ltrs (9-10 pints) - how often do you change your oil (how many hours) 50 hrs (oops sometimes a "little" longer:-)) At lease every 6 mths in time regardless of hours & always new filter(s) - how often does the manufacturer recommend you change the oil? NA - Does your motor burn or lose oil? Do you have to top up in between oil changes? no/no Thanks for your help! welcome:-) K Matt |
"Doug Kanter" wrote in message ...
"Matt Lang" wrote in message om... Guys, I am trying to find out how much more (or less) oil a 2 stroke uses compared to a 4 stroke. Thus, I need to know about your 4 stroke motor (inboard or outboard): - Horsepower, brand - amount of oil it takes for an oil change (incl filter) - how often do you change your oil (how many hours) - how often does the manufacturer recommend you change the oil? - Does your motor burn or lose oil? Do you have to top up in between oil changes? Thanks for your help! Matt Don't have specs in front of me, so I can only answer the last question regarding my Johnson 1996 15 hp 4 stroke (model J15FREDR). It consumes NO oil between April and November. Zero. I change it twice during that time period, and based on memory, that's about twice as often as OMC recommends. Ok :) How much oil do you need for an oil change? Matt |
"K. Smith" wrote in message ...
Matt Lang wrote: Guys, I am trying to find out how much more (or less) oil a 2 stroke uses compared to a 4 stroke. Thus, I need to know about your 4 stroke motor (inboard or outboard): - Horsepower, brand 80/na - amount of oil it takes for an oil change (incl filter) 6 ltrs (9-10 pints) - how often do you change your oil (how many hours) 50 hrs (oops sometimes a "little" longer:-)) At lease every 6 mths in time regardless of hours & always new filter(s) - how often does the manufacturer recommend you change the oil? NA - Does your motor burn or lose oil? Do you have to top up in between oil changes? no/no Thanks for your help! welcome:-) K Matt Thanks to you guys for the data! Keep 'em coming! I think its safe to say that if you do run your motor only few hours a year, like 10-20, a 2 stroke may actually consume less oil. It will change the more you run it ... Still more data needs to be collected. A 4 stroke that burns oil, and I was told for cars 1l per 1000 km is considered no defect (by the manufacturer of course! The owner sees it differently) will use quiet a bit of oil. :) Matt |
Matt Lang wrote:
"K. Smith" wrote in message ... Matt Lang wrote: Guys, I am trying to find out how much more (or less) oil a 2 stroke uses compared to a 4 stroke. Thus, I need to know about your 4 stroke motor (inboard or outboard): - Horsepower, brand 80/na - amount of oil it takes for an oil change (incl filter) 6 ltrs (9-10 pints) - how often do you change your oil (how many hours) 50 hrs (oops sometimes a "little" longer:-)) At lease every 6 mths in time regardless of hours & always new filter(s) - how often does the manufacturer recommend you change the oil? NA - Does your motor burn or lose oil? Do you have to top up in between oil changes? no/no Thanks for your help! welcome:-) K Matt Thanks to you guys for the data! Keep 'em coming! I think its safe to say that if you do run your motor only few hours a year, like 10-20, a 2 stroke may actually consume less oil. It will change the more you run it ... Still more data needs to be collected. A 4 stroke that burns oil, and I was told for cars 1l per 1000 km is considered no defect (by the manufacturer of course! The owner sees it differently) will use quiet a bit of oil. :) Matt Save you do huge hours per season I doubt a 4 stroke would "use" less oil than one of the new epa compliant 2 strokes but you might also consider; (i) The 4 stroke doesn't put oil out into the air or the water, it gets "changed". Hopefully the used oil gets disposed of correctly, here that's mostly take it to a garage for their recycle tanks. (ii) You should at least once a season clean out the oil reservoir on the 2 strokes (new or old type), the oil in a vented tank absorbs moisture which creates a sludge in the bottom of the tank. (iii) The "new" 2 strokes use or at least recommend special dealer only oils; can be expensive. K |
I am probably a heavy user here, about 300-350 hours a year in a 12 month
boating season. I change my oil 4 times a year, using 3 quarts a change and none between. At that rate I am using a lot less oil than I did with a 2 stroke. It also gets recycled. Figure your oil goes in at 50:1 in a 2 stroke, my 60 uses 3 quarts so I could burn 37.5 gallons of mix but since you usually use a pint per 6 gallon can it is really 36.125 gallons. That would only last me about 10 hours at a moderate cruise speed. The oil saving for me is 90% over a 2 stroke. I could even save more if I used auto oil instead of Merc brand.. If you also add in the actual fuel efficiency it is greater than that. I bet the saving is even greater when you get up into the big Vs. His 6 quart oil change would "mix" about 72 gallons of gas. A 250 2 stroke could easily burn that on one day's offshore fishing trip. |
"Matt Lang" wrote in message om... "Doug Kanter" wrote in message ... "Matt Lang" wrote in message om... Guys, I am trying to find out how much more (or less) oil a 2 stroke uses compared to a 4 stroke. Thus, I need to know about your 4 stroke motor (inboard or outboard): - Horsepower, brand - amount of oil it takes for an oil change (incl filter) - how often do you change your oil (how many hours) - how often does the manufacturer recommend you change the oil? - Does your motor burn or lose oil? Do you have to top up in between oil changes? Thanks for your help! Matt Don't have specs in front of me, so I can only answer the last question regarding my Johnson 1996 15 hp 4 stroke (model J15FREDR). It consumes NO oil between April and November. Zero. I change it twice during that time period, and based on memory, that's about twice as often as OMC recommends. Ok :) How much oil do you need for an oil change? Matt What's the difference? :-) I mean, are you collecting this information in order to make a purchase decision? Or, what? |
Matt Lang wrote:
Guys, I am trying to find out how much more (or less) oil a 2 stroke uses compared to a 4 stroke. Thus, I need to know about your 4 stroke motor (inboard or outboard): - Horsepower, brand Ford-based Palmer Crusader ThermoElectron 220 hp V-8 - amount of oil it takes for an oil change (incl filter) 5 qts. inc filter, @ $4.09 qt. for Mobil 1 - how often do you change your oil (how many hours) 45-50 hrs. - how often does the manufacturer recommend you change the oil? 100 hrs - Does your motor burn or lose oil? No. Do you have to top up in between oil changes? No. At about 6 gal/hr. on average, we are "using" about the same amount of oil per hour, at about $2.05/pt., as our Glastron/115 hp Evinrude which also uses about 6 gal/hr of 50:1 in normal mixed use. It's just about a wash with us - both are 16' fiberglass boats - unless we start using the inboard more (which we probably will as the kids start skiing more). When we were using the Glastron 100-120 hrs. / year, and snowmobiling all winter, we bought a 55 gallon drum of Kendall 2 stroke. That was a big money saver... it kills me to pay retail for oil now... Rob |
On Fri, 19 Nov 2004 15:07:33 GMT, "Doug Kanter"
wrote: "Matt Lang" wrote in message . com... "Doug Kanter" wrote in message ... "Matt Lang" wrote in message om... Guys, I am trying to find out how much more (or less) oil a 2 stroke uses compared to a 4 stroke. Thus, I need to know about your 4 stroke motor (inboard or outboard): - Horsepower, brand - amount of oil it takes for an oil change (incl filter) - how often do you change your oil (how many hours) - how often does the manufacturer recommend you change the oil? - Does your motor burn or lose oil? Do you have to top up in between oil changes? Don't have specs in front of me, so I can only answer the last question regarding my Johnson 1996 15 hp 4 stroke (model J15FREDR). It consumes NO oil between April and November. Zero. I change it twice during that time period, and based on memory, that's about twice as often as OMC recommends. Ok :) How much oil do you need for an oil change? What's the difference? :-) I mean, are you collecting this information in order to make a purchase decision? Or, what? Matt is a spy for Halliburton. Later, Tom ----------- "Angling may be said to be so like the mathematics that it can never be fully learnt..." Izaak Walton "The Compleat Angler", 1653 |
"K. Smith" wrote in message ...
Matt Lang wrote: Save you do huge hours per season I doubt a 4 stroke would "use" less oil than one of the new epa compliant 2 strokes but you might also consider; I will create some charts and post ... Besides the ETEC they all use lots of oil . My optimax runs at 50:1 - 60:1 :( (i) The 4 stroke doesn't put oil out into the air or the water, it gets "changed". Hopefully the used oil gets disposed of correctly, here that's mostly take it to a garage for their recycle tanks. Yes true ... this time however cost is the only objective ;) I am unsure which is worse: 2 stroke oil burnt or 4 stroke oil in the landfills in form of oily rags and filters which most people dont dispose properly (assuming they recycle the actual oil) (ii) You should at least once a season clean out the oil reservoir on the 2 strokes (new or old type), the oil in a vented tank absorbs moisture which creates a sludge in the bottom of the tank. Yikes! I didnt know that ... how is that done? flush it with oil? (iii) The "new" 2 strokes use or at least recommend special dealer only oils; can be expensive. They ARE very expensive. Although you can run an optimax on the (relatively) cheap oil it is STRONGLY not recommended .... Thanks for your good input! Matt |
What's the difference? :-) I mean, are you collecting this information in
order to make a purchase decision? Or, what? Matt is a spy for Halliburton. Later, Tom Dont tell them! Not everybody needs to know ;) |
Ok :) How much oil do you need for an oil change? Matt What's the difference? :-) I mean, are you collecting this information in order to make a purchase decision? Or, what? I have 200 HP 2 stroke and just want to feel better by knowing how much oil a 4stroke uses ;) Matt Look here for a chart 2 stroke vs. 4 stroke http://img56.exs.cx/img56/2093/oil.jpg |
Matt Lang wrote:
Ok :) How much oil do you need for an oil change? Matt What's the difference? :-) I mean, are you collecting this information in order to make a purchase decision? Or, what? I have 200 HP 2 stroke and just want to feel better by knowing how much oil a 4stroke uses ;) Matt Look here for a chart 2 stroke vs. 4 stroke http://img56.exs.cx/img56/2093/oil.jpg Had a look at the chart, what's the issue??? It confirms that the modern 2 strokes use less oil than the older ones, but this is an allusion really when you take into account the extra costs & while the dealers won't admit it you "should" clean the holding tank every year. Once in there oil subject to heat & moisture deteriorates into sludge with even the smallest amounts of water. Again "all" the oil in a 2 stroke (by your graph the same or more than a 4 stroke) still goes somewhere, either burnt or out the exhaust as raw oil, I accept what you say about oily rags etc but we're talking the entirety of the oil, not just sundry cleanup wipes. There is another issue with the dfi 2 strokes & their oil, it's related to raw oil injected into the crankcase, the oil builds up till excess is "transferred", it either then gets burnt or goes straight through the exhaust as raw oil. The system injects very small amounts at idle or even low revs, however the oil is subject to considerable heat buildup, unlike 4 strokes oil or even an old tech 2 stroke when it was diluted with fuel & traveled through the engine relatively quickly. This is why they've promoted special oils, because the oil can get hot enough to bake behind the rings & it's all down hill from there. Harry is a liar & has never actually owned a boat much less an optimax engine. As for his old "hundreds of hours" lie, when he fabricated that phantom boat in 98 he claimed here after a few mths use he had 200 hours on it, it's just more evidence of a total lie. K |
Harry Krause wrote:
K. Smith wrote: Had a look at the chart, what's the issue??? It confirms that the modern 2 strokes use less oil than the older ones, but this is an allusion really when you take into account the extra costs & while the dealers won't admit it you "should" clean the holding tank every year. An allusion, eh? An allusion is a pun. And how about providing some legitimate cites that indicate modern two stroke oil tanks need to be cleaned every year. Cites from manufacturers, refineries, et cetera. Not your illusional bull. I don't need any; my "bull" about these experimental engines has be spot on since they were released, we said they'd fail & they did, but most importantly we explained why & all actions by the spruikers still trying to sell them have confirmed us as correct (NB "us/we" I've never claimed & still don't that this is my personal work, my "blokes" include some clever engineers & we have some local knowledge of orbital) One of the defects in all the oil injection 2 stroke systems is the fact the oil can sit in a vented tank for season after season, particularly in cold climates this is lunacy, always has been even pre dfi, of course if they admit it then their oil usage spruiking line goes in the bin with the unused oil:-) So gee it's only a small risk & after all we can blame the customer, or the oil or walmart:-). Even a 4 stroke nobody would say oil can last years in the sump even if you don't use the engine, it will absorb moisture. I'm proud there are no "cites" about the defects in the DFIs, because I copped endless abuse from you & the dealers when I warned you years in advance exactly what was going to happen. Of course you defenders all had vested motives, the dealers?? turns out despite their lies they were getting up to 30% "rebates" to keep flogging known defective motors & you?? you work for a union investment fund who was in bed with Soros, so you helped to rip off not just boaters, but thousands of genuine workers who were reliant upon their pensions. Once in there oil subject to heat & moisture deteriorates into sludge with even the smallest amounts of water. This from a woman who has never even seen a modern two stroke outboard? Hmm you wish:-) You post any cite from anywhere that predates mine in this newsgroup warning they would fail & importantly explaining why. There is another issue with the dfi 2 strokes & their oil, it's related to raw oil injected into the crankcase, the oil builds up till excess is "transferred", it either then gets burnt or goes straight through the exhaust as raw oil. The system injects very small amounts at idle or even low revs, however the oil is subject to considerable heat buildup, unlike 4 strokes oil or even an old tech 2 stroke when it was diluted with fuel & traveled through the engine relatively quickly. This is why they've promoted special oils, because the oil can get hot enough to bake behind the rings & it's all down hill from there. Ahhh...the manufacturers suggest using special oils to avoid a problem. How clever of them, eh? Well it's confirmation that exactly what we warned of from the beginning is true, just as the latest attempts with "special" alloy in the pistons?? this is a hoot!!! & now a "sensor" (read knock sensor:-)) to sense "abnormal combustion" the standard euphemism for detonation:-) Yes they've taken 7 yrs to confirm that they now accept the nature of the problem, the problem they denied year after year even existed!!! even as huge Cos went broke on account of it. Trouble is it still won't work!!! they're trying to treat the symptom by making the oil higher temp tolerant, the pistons so they won't melt till a higher temp & the injection so it can try to "adjust" to the detonation. However the root cause remains; at power overly lean, poorly atomised mixtures are unreliable & will lead to an engine failure rate too high for consumer usage, sure not ever single engine just the odd one here & there is plenty. They admitted to 1 in 5 but 1 in 100 is still too high, imagine if 1 in 100 ford engines failed:-). Just to be absolutely sure they get a high failure rate they've added crazy continuous fire ignition & a marginal lubrication system. Seems the big engine manufacturers were right to reject Ficht & orbital as amateurs, at least merc have seen the light & will be rid of them, not soon enough but still. As for the latest get rich quick mob using consumers as engine test dummies?? well you've heard it here first.... again:-) Harry is a liar & has never actually owned a boat much less an optimax engine. As for his old "hundreds of hours" lie, when he fabricated that phantom boat in 98 he claimed here after a few mths use he had 200 hours on it, it's just more evidence of a total lie. K Ms. Smith, I know you're hurting, and hurting badly, but nature does take its toll, and you'll just have to drop your prices. I don't think the foreign sailors coming into your home port will cough up the two bits you used to charge... Thanks Krause a bit of that sort of abuse certainly confirms your lies, which you just keep telling. Now please have yet another go at setting your killfile so you don't keep answering me, I'm happy with that. If you don't know how to do it properly just email mail me as above but at tpg com au & I'll gladly assist . K |
"Matt Lang" wrote in message om... Ok :) How much oil do you need for an oil change? Matt What's the difference? :-) I mean, are you collecting this information in order to make a purchase decision? Or, what? I have 200 HP 2 stroke and just want to feel better by knowing how much oil a 4stroke uses ;) That makes no sense at all. :-) Once you know, are you going to replace your 2-stroke? |
"K. Smith" wrote in message
... Harry is a liar & has never actually owned a boat much less an optimax engine. As for his old "hundreds of hours" lie, when he fabricated that phantom boat in 98 he claimed here after a few mths use he had 200 hours on it, it's just more evidence of a total lie. K, you really need to stop blowing kangaroos as a hobby. |
"Matt Lang" wrote
I have 200 HP 2 stroke and just want to feel better by knowing how much oil a 4stroke uses ;) The quantity of oil needed to operate a modern oil-injected 2 stroke engine is pretty darn similar to that needed to operate an equivalent 4 stroke. There. Feel better? |
Stick with the two stroke. TWO STROKES RULE!!!! Dont have to tell me, I have 200 s troke HP powering my boat ;) Look here for a chart 2 stroke vs. 4 stroke http://img56.exs.cx/img56/2093/oil.jpg I know I'm kind of slow, but what exactly is that chart supposed to illustrate? it shows that if you use your motor very little (which you shouldnt!) you will have used less oil with the 2 stroke as you had with the 4 stroke. It also shows that about 55h run time a 2 stroke will use AS MUCH oil as a 4 stroke NOT MORE. This is based on 200 HP Merc optimax vs 200 HP Merc verado and a few other assumptions. It shows a (who makes them now?) ETect which uses almost under all circumstances less oil as a 4 stroke. This is all based at 4250 ROM average and does not show anything else like environmental or cost issues. I looked into this to find out if I have to feel sorry for buying a 2 stroke and burning ****loads of oil or if there is little difference. I am happy with my decission to get the DFI Matt |
http://img56.exs.cx/img56/2093/oil.jpg
There is something seriously flawed with this chart. To start with they are changing ooil at 50 hours. My merc says 100 hours. The other thing is are they really saying a 200 hp 2s engine can run 100 hours on 20 quarts of oil? That's 5 gallons and even at 100:1 that is only 5 gallons of fuel per hour. Are these hours being put on at idle speed? I know a lot of guys with 200s and they would kill to get 5 GPH at any decent cruise speed. I also think these motors use more like 50:1 at high speed. The 100:1 is at idle. I have a neighbor with an Optimax. I will ask him how long a gallon of oil lasts him. I know I gave him 2 gallons when I bought my 4 stroke and he didn't act like it was a lifetime supply. |
Had a look at the chart, what's the issue??? No issue, i just wanted to see how much oil the 2 stroke actually used. The benchmark is a 4 stroke motor which is usually is not known as "uses oil". I didnt want to fel bad ripping around burning loads of oil, thus I want to see how much i am useing compared to if I had bought a 4 stroke. The boat and the other motorized toys are getting winterized :((( So I have lots of time on my hand for these kind of questions ;) It confirms that the modern 2 strokes use less oil than the older ones, but this is an allusion really when you take into account the extra No, actually it doeasnt, unless you consider the optimax old desogn. The optimax is an older design and the first generation DFI. Lets see to how many generations they will actually make it ... The chart shows Merc Optimax, Whoevers (Bombardier?) ETec, and Mercs 4 stroke Verado. The oldest design there is the optimax. All of the above use less oil as a conventional 2 stroke. costs & while the dealers won't admit it you "should" clean the holding tank every year. Once in there oil subject to heat & moisture deteriorates into sludge with even the smallest amounts of water. This is a very good point which I will investigate right away in order to keep my motor happy :) This flushing procedure can be done with cheap oil or maybe other suitable substances. Do you have any procedure or recommendation? In the end it may be cheaper to buy a new oil tank? This needs to be looked into. Again "all" the oil in a 2 stroke (by your graph the same or more than a 4 stroke) still goes somewhere, either burnt or out the exhaust as raw oil, I accept what you say about oily rags etc but we're talking the entirety of the oil, not just sundry cleanup wipes. Yes correct. This point was not looked at in my comaprison and was not intended to be looked at. It is a very important and valid point though. Someone needs to create an eco balance to see whats worse in the end. If 4 stroke oil is recycled then thats best. If its done like some people I know do by not recycling or just recycling the oil but not the filter and rags then it maybe worse than the 2 stroke just burning it up. There is another issue with the dfi 2 strokes & their oil, it's related to raw oil injected into the crankcase, the oil builds up till excess is "transferred", it either then gets burnt or goes straight through the exhaust as raw oil. I see no serious issue. Exactly that happens with conventional 2 strokes ... of course in general its not good that 2 strokes burn oil .... The system injects very small amounts at idle or even low revs, however the oil is subject to considerable heat buildup, unlike 4 strokes oil or even an old tech 2 stroke when it was diluted with fuel & traveled through the engine relatively quickly. This is why they've promoted special oils, because the oil can get hot enough to bake behind the rings & it's all down hill from there. Yes the DFI motors need the expensive oil. I only know the optimax and it partly recycles its oil, which is good but this requires different oil then the normal 2 stroke uses which is bad, as the recirculated oil must be made so it doesnt break down from it (expensive). Harry is a liar & has never actually owned a boat much less an optimax engine. As for his old "hundreds of hours" lie, when he fabricated that phantom boat in 98 he claimed here after a few mths use he had 200 hours on it, it's just more evidence of a total lie. Its not for me to judge that. I can not see a reason that would make people claim they have owned certain boats and motors which they actually havent. But to each their own. Karen, I appreciate the discussion with you and the points you bring in! You seem to be more knowledgable about the subject as ... lets say .... the average female (and in fact male)... Dont take this wrong, this isnt sexist talk! Whats your background and your background with motors if I may ask? You are also welcome to email me. My email as posted is real. Matt |
On 21 Nov 2004 04:49:52 GMT, (Greg) wrote:
http://img56.exs.cx/img56/2093/oil.jpg There is something seriously flawed with this chart. To start with they are changing ooil at 50 hours. My merc says 100 hours. The other thing is are they really saying a 200 hp 2s engine can run 100 hours on 20 quarts of oil? That's 5 gallons and even at 100:1 that is only 5 gallons of fuel per hour. Are these hours being put on at idle speed? I know a lot of guys with 200s and they would kill to get 5 GPH at any decent cruise speed. I also think these motors use more like 50:1 at high speed. The 100:1 is at idle. I have a neighbor with an Optimax. I will ask him how long a gallon of oil lasts him. I know I gave him 2 gallons when I bought my 4 stroke and he didn't act like it was a lifetime supply. My Contender, at cruise with FICHT 225s, uses about 8 Gph per engine averaged after the trip which accounts for idle time. I rarely run WOT. At idle or trolling speeds, 5 Gph isn't unheard of. My Ranger which has a FICHT 200 gets 5 Gph all round - it has never varied from day one. Later, Tom |
On 20 Nov 2004 19:20:52 -0800, (Matt Lang) wrote:
Stick with the two stroke. TWO STROKES RULE!!!! Dont have to tell me, I have 200 s troke HP powering my boat ;) Look here for a chart 2 stroke vs. 4 stroke http://img56.exs.cx/img56/2093/oil.jpg I know I'm kind of slow, but what exactly is that chart supposed to illustrate? it shows that if you use your motor very little (which you shouldnt!) you will have used less oil with the 2 stroke as you had with the 4 stroke. It also shows that about 55h run time a 2 stroke will use AS MUCH oil as a 4 stroke NOT MORE. This is based on 200 HP Merc optimax vs 200 HP Merc verado and a few other assumptions. It shows a (who makes them now?) ETect which uses almost under all circumstances less oil as a 4 stroke. This is all based at 4250 ROM average and does not show anything else like environmental or cost issues. I looked into this to find out if I have to feel sorry for buying a 2 stroke and burning ****loads of oil or if there is little difference. I am happy with my decission to get the DFI Thanks - I wasn't sure that all that was. It was pretty though. :) I actually had to be talked into my first FICHT on the Ranger, but ever since, I'm convinced. Later, Tom |
On Sat, 20 Nov 2004 23:36:32 -0800, Matt Lang wrote:
Again "all" the oil in a 2 stroke (by your graph the same or more than a 4 stroke) still goes somewhere, either burnt or out the exhaust as raw oil, I accept what you say about oily rags etc but we're talking the entirety of the oil, not just sundry cleanup wipes. Yes correct. This point was not looked at in my comaprison and was not intended to be looked at. It is a very important and valid point though. Someone needs to create an eco balance to see whats worse in the end. If 4 stroke oil is recycled then thats best. If its done like some people I know do by not recycling or just recycling the oil but not the filter and rags then it maybe worse than the 2 stroke just burning it up. This is the Major Issue with me, and why I went 4-stoke. I can recycle the crankcase oil when I change it, not spew it out into my favourite pristine lake. Also, my "ultralight" Merc 9.9 uses just under 1 litre of oil in the crankcase. Lloyd Sumpter "The Tin Boat" Mirrocraft 12 |
(Greg) wrote in message ...
http://img56.exs.cx/img56/2093/oil.jpg There is something seriously flawed with this chart. To start with they are changing ooil at 50 hours. My merc says 100 hours. I didnt know that .. that would indeed offset this a little ... The other thing is are they really saying a 200 hp 2s engine can run 100 hours on 20 quarts of oil? That's 5 gallons and even at 100:1 that is only 5 gallons of fuel per hour. Are these hours being put on at idle speed? I know a lot of The 2 stroke is posted at 4250 RPM and my 200 HP 2 stroke gets 5.8 MPG at cruise. The oils is based on that and an average of 65:1 guys with 200s and they would kill to get 5 GPH at any decent cruise speed. I also think these motors use more like 50:1 at high speed. The 100:1 is at idle. I get 4.8 US gallon per hour at cruise at 28 MPH ... 200 2 stroke HP ! I have a neighbor with an Optimax. I will ask him how long a gallon of oil lasts him. I know I gave him 2 gallons when I bought my 4 stroke and he didn't act like it was a lifetime supply. Mine uses .3l per hour at cruise ... whu knows how many gallosn this are. Dont forget this chart isnt religion, I just put it together for myself to see how bad the oil use really is.. Take it for that and not more. Matt |
Short Wave Sportfishing wrote in message . ..
On 20 Nov 2004 19:20:52 -0800, (Matt Lang) wrote: Stick with the two stroke. TWO STROKES RULE!!!! Dont have to tell me, I have 200 s troke HP powering my boat ;) Look here for a chart 2 stroke vs. 4 stroke http://img56.exs.cx/img56/2093/oil.jpg I know I'm kind of slow, but what exactly is that chart supposed to illustrate? it shows that if you use your motor very little (which you shouldnt!) you will have used less oil with the 2 stroke as you had with the 4 stroke. It also shows that about 55h run time a 2 stroke will use AS MUCH oil as a 4 stroke NOT MORE. This is based on 200 HP Merc optimax vs 200 HP Merc verado and a few other assumptions. It shows a (who makes them now?) ETect which uses almost under all circumstances less oil as a 4 stroke. This is all based at 4250 ROM average and does not show anything else like environmental or cost issues. I looked into this to find out if I have to feel sorry for buying a 2 stroke and burning ****loads of oil or if there is little difference. I am happy with my decission to get the DFI Thanks - I wasn't sure that all that was. It was pretty though. :) yes it is .. its not to be overrrated :) I actually had to be talked into my first FICHT on the Ranger, but ever since, I'm convinced. FICHT's had many problems but the now ETecs seem to be very interesting motors to say the least! I hope Merc and Yamaha will try to top them. I am glad that your FICHTS work well :) Matt |
Lloyd Sumpter wrote in message .. .
On Sat, 20 Nov 2004 23:36:32 -0800, Matt Lang wrote: Again "all" the oil in a 2 stroke (by your graph the same or more than a 4 stroke) still goes somewhere, either burnt or out the exhaust as raw oil, I accept what you say about oily rags etc but we're talking the entirety of the oil, not just sundry cleanup wipes. Yes correct. This point was not looked at in my comaprison and was not intended to be looked at. It is a very important and valid point though. Someone needs to create an eco balance to see whats worse in the end. If 4 stroke oil is recycled then thats best. If its done like some people I know do by not recycling or just recycling the oil but not the filter and rags then it maybe worse than the 2 stroke just burning it up. This is the Major Issue with me, and why I went 4-stoke. I can recycle the crankcase oil when I change it, not spew it out into my favourite pristine lake. Also, my "ultralight" Merc 9.9 uses just under 1 litre of oil in the crankcase. Lloyd Sumpter "The Tin Boat" Mirrocraft 12 Yes thats a point. However apparently 2 stroke oil buns up and shouldnt be as harmful as unburnt oil.... I would like to see real data about that. Matt |
Matt Lang wrote:
Had a look at the chart, what's the issue??? No issue, i just wanted to see how much oil the 2 stroke actually used. The benchmark is a 4 stroke motor which is usually is not known as "uses oil". I didnt want to fel bad ripping around burning loads of oil, thus I want to see how much i am useing compared to if I had bought a 4 stroke. The boat and the other motorized toys are getting winterized :((( So I have lots of time on my hand for these kind of questions ;) It confirms that the modern 2 strokes use less oil than the older ones, but this is an allusion really when you take into account the extra No, actually it doeasnt, unless you consider the optimax old desogn. The optimax is an older design and the first generation DFI. Lets see to how many generations they will actually make it ... The chart shows Merc Optimax, Whoevers (Bombardier?) ETec, and Mercs 4 stroke Verado. The oldest design there is the optimax. All of the above use less oil as a conventional 2 stroke. costs & while the dealers won't admit it you "should" clean the holding tank every year. Once in there oil subject to heat & moisture deteriorates into sludge with even the smallest amounts of water. This is a very good point which I will investigate right away in order to keep my motor happy :) This flushing procedure can be done with cheap oil or maybe other suitable substances. Do you have any procedure or recommendation? In the end it may be cheaper to buy a new oil tank? This needs to be looked into. I wouldn't think "flushing" would be needed indeed the suggestion here is not to risk touching the existing hose fittings etc for fear of creating a leak. Also even a small air lock can be trouble. Again "all" the oil in a 2 stroke (by your graph the same or more than a 4 stroke) still goes somewhere, either burnt or out the exhaust as raw oil, I accept what you say about oily rags etc but we're talking the entirety of the oil, not just sundry cleanup wipes. Yes correct. This point was not looked at in my comaprison and was not intended to be looked at. It is a very important and valid point though. Someone needs to create an eco balance to see whats worse in the end. If 4 stroke oil is recycled then thats best. If its done like some people I know do by not recycling or just recycling the oil but not the filter and rags then it maybe worse than the 2 stroke just burning it up. There is another issue with the dfi 2 strokes & their oil, it's related to raw oil injected into the crankcase, the oil builds up till excess is "transferred", it either then gets burnt or goes straight through the exhaust as raw oil. I see no serious issue. Exactly that happens with conventional 2 strokes ... of course in general its not good that 2 strokes burn oil ... A conventional 2 stroke even an efi that injects raw oil, still "mixes" it with fuel in the crankcase & it's in those premises that I was suggesting the oil itself doesn't get the chance to lie around getting hot, whereas the situation is slightly different with the DFIs, it can & does. The system injects very small amounts at idle or even low revs, however the oil is subject to considerable heat buildup, unlike 4 strokes oil or even an old tech 2 stroke when it was diluted with fuel & traveled through the engine relatively quickly. This is why they've promoted special oils, because the oil can get hot enough to bake behind the rings & it's all down hill from there. Yes the DFI motors need the expensive oil. I only know the optimax and it partly recycles its oil, which is good but this requires different oil then the normal 2 stroke uses which is bad, as the recirculated oil must be made so it doesnt break down from it (expensive). Harry is a liar & has never actually owned a boat much less an optimax engine. As for his old "hundreds of hours" lie, when he fabricated that phantom boat in 98 he claimed here after a few mths use he had 200 hours on it, it's just more evidence of a total lie. Its not for me to judge that. I can not see a reason that would make people claim they have owned certain boats and motors which they actually havent. But to each their own. Karen, I appreciate the discussion with you and the points you bring in! You seem to be more knowledgable about the subject as ... lets say ... the average female (and in fact male)... Dont take this wrong, this isnt sexist talk! Whats your background and your background with motors if I may ask? When the DFI were released we (we is the blokes I work with) took a particular interest because for literally years before we'd been watching Orbital the promoters of the optimax system, & Ficht trying to flog their systems around the major engine manufacturers. Ficht was originally promoted as a diesel injection system & orbital even got Ford to run a test fleet of small cars on orbital 2 strokes. Particularly Orbital in our view were all froth & bubble they made extravagant claims in the local press releases it seemed every second Wednesday; they claimed Ford were about to adopt it, then even the son of the bent Indonesian ruler at the time Sohato was said to be going to build cars with orbital engines & teach Detroit a thing or two:-) it would have been hilarious had it not sucked endless sad investors of their money. Never once would Orbital deal with the common call from almost everyone in the local industry of "how do you say you've dealt with the problem of heat buildup when engines are run lean???", they usually muttered something about extra atomisation happening in that primary manifold from the air pump, however it didn't work. We also watched their patent applications closely (when I say we we're "interested" I mean we had a definite interest:-)). After a while & particularly after Ford dismissed it as nonsense, we noticed most of their filings were related to solutions to problems that were of their own making, indeed we felt every ad hoc "fix" they seemed to dream up would just lead to more questions than solutions. As for Ficht it was much more easily identified as doomed, it's original patents involved pumping fuel (diesel in this case) around a closed rail at high velocity, then electromagnetically slamming a valve shut in it's path, the impact shock created pressure waves in the system (exactly like water pipe hammer when the washing machine valve slams shut) they claimed the peaks of which could be harvested by an injector nozzle. Of course anyone who knew the slightest about the amount of energy & force needed to create sudden extreme pressure rises, that could be sustained over the period of time a diesel needs to inject fuel, immediately dismissed it as nonsense (Germany the home of fuel injection didn't even give it a second glance). The Ficht principle is the same as water hammer in domestic plumbing or pressure spikes in hydraulic systems i.e. very well known & understood, it's a bother & can cause damage but as soon as there's an outlet for "spikes" (usually a simple damper) the pressure goes away. Ficht is an attempt to get a great pressure rise over a very short period & do it essentially for no energy input. Something for nothing??? not likely in this universe as we currently know it:-) We were more than a little bemused when Brunswick & OMC announced they had signed up with orbital & ficht respectively, the orbital was as it was & the Ficht they'd changed the execution so instead of suddenly stopping fuel at high velocity they just struck a solid ball to great the shock waves.A bit like dropping a rock in a bucket of water, the waves created go over the edge. Ficht failed spectacularly as predicted because the impact pressure rise was never going to supply enough pressure rise to give proper atomisation, coupled with the lean mixtures it had a serious failure rate & as I said was doomed from the beginning. Optimax faired a little better but still had the problem of low injection pressure (they use a normal injector pressure but unlike a normal injector into a vehicle manifold (which is usually below atmospheric pressure) they inject against the pressure of the output from the additional air pump, so the atomisation problem remains, as does the question of lean mixture heat buildup. Both technologies are by now totally discredited, Brunswick are clearly going 4 stroke throughout the range & Ficht brought OMC down, then Bomb (who have some proper engineers) got rid of it, now in a last desperate gasp E-tec will try to mitigate against the symptoms by using ever more heat resistant oil & pistons that will not "melt" till a higher temp:-) Sorry to smile but it's absurd!!! if petrol sees any temp around or above 250C it auto ignites (detonates), even the lowliest of aluminium is good to well over 600C. So their latest suck it & see try is as doomed as the original Fichts & for the exact same reasons; (i) The impact shock injectors can never create enough pressure to properly atomise the fuel (Yamaha need 800 psi & they are also going to 4 strokes). (ii) The so called injector is not an injector at all but not much better than a flap valve/garden hose nozzle, it will only open when the combustion chamber pressure is well below the pressure in the shock injectors. At power they "try" to start injection up to 240degs BTDC i.e. before the previous charge has even uncovered the exhaust ports. (iii) The continuous firing of the spark is just the same confirmation of how lean the mix is at low to med revs & of course it means accurate timing of the actual ignition point is impossible, this means some firing will be as intended others very late, just so long as there isn't a "miss" because then they fail the EPA. (iv) The latest sensor to detect abnormal combustion (knock sensor) is proof positive they're well aware of the issue, however it's also proof they still don't understand the real cause of the engine failures. (v) It's long been known (mainly from aircraft engines, but also some attempts with car engines Chrysler, Honda & Mitsubishi) that engine can run on very lean mixtures, however the "abnormal" combustion leads to heat buildup in the chamber surfaces. Usually an engine running very lean will not detonate while still extremely lean (i.e. their latest sensor will not sense anything), but this doesn't stop the chamber surfaces getting overly hot. (vi) In an OB 2 stroke the head can be kept very cool being alloy & having an endless supply of cool water, but the piston/rings in a 2 stroke is almost totally uncooled. Once the piston temps gets over 250C (not very hot really) then auto ignition is a certainty but while lean probably no harm done, simply because there isn't enough fuel present. (vii) The trouble starts when the power is quickly increased above the lean burn mode, suddenly there is plenty of fuel available & this sudden excess fuel rather than cool the piston just auto ignites but now it will lead to full on detonation = more heat = more detonation etc etc bang. (viii) Their new sensor will detect this but what can it really do??? retard the spark timing?? too late the overly hot piston is causing the auto ignition not the spark timing; increase the mixture??? again too late it's the sudden influx of fuel onto the overly hot surface that set the full detonation going in the first place; what's left?? electronically lower the power?? well consumers won't be impressed with their engine slowing when they suddenly give it full throttle. It's instructive to see how the same lean mixtures problem has been approached by others over many years; (a) The car people Chrysler, Honda, Mitsubishi & Mercedes have all gone to extreme lengths to guard against excess heat being built up while the engine is in lean mode, mostly this limits lean mixtures to idle (no power at all) over run, (No power at all & boat motors don't have it anyway) or very light throttle high speed cruise (again hardly any power at all, most cars it's when the EGR (exhaust gas recirculation) is engaged, so the average modern slippery sedan needs about 30hp to hold it at 65mph (flat road blah blah blah) & this is usually around 1800-2000 rpm or 12-15% of max power at about 35-40% of max revs i.e. the cyl pressure is extremely low with lots of air (& exhaust) going through keeping the chamber cool. (a boat motor has no very light load high speed cruise, as the revs rise so does the load from the prop it increases at a steepening rate) All these precautions yet they're all 4 strokes (half the number of firings & plenty of oil under the piston to carry the heat away). (b) The piston aircraft engines are also run lean although never anything like as lean as Ficht & Optimax claim. Aircraft lean as the air density lowers with altitude so they're not really very lean at all & allowing that they're big slow turning essentially lazy engines, even so they still run the risk of having heat buildup in the chamber when operated too lean, so pilots are trained never to recover from lean cruising by just giving the engine full rich mixture & more throttle (exactly what happens when an OB is suddenly powered up after a long run in the lean mode). Pilots are trained to richen the mixture slowly as the power is slowly increased, this is to give the chamber temps time to normalise as the extra fuel is added; just in case:-) You are also welcome to email me. My email as posted is real. Sorry to be so long again, but this subject has been a war since 98 & it seems till Brunswick are all 4 stroke & E-tec has failed it will continue. Mine isn't; the name is OK but it's tpg com au K Matt |
On Mon, 22 Nov 2004 23:23:19 +1100, "K. Smith"
wrote: ~~ snippage ~~ Sorry to be so long again, but this subject has been a war since 98 & it seems till Brunswick are all 4 stroke & E-tec has failed it will continue. Ah - now I understand the reasons for your antipathy towards FICHT. NIcely put by the way. I don't agree based on my own personal experience with FICHTS and what I know about them pre/post-OMC, but you have reasons and that's fine. It was interesting. :) I'm curious though. Your argument about diesel makes some sense - essentially, FICHT (and Etec for that matter) is diesel technology. Without going into a long treatise on the subject, I assume your contention is that FICHT is not a true two stroke and as such, problematic in the long run? Later, Tom |
Unfortunately the lack of background does not stop her basic research from being more correct than not on a theoretical / technical level. The DFI motors do have some inherant lean burn issues. Issues that have been sucessfully "worked around" by throwing more electronics and technology at them, but still loom over the design concept as a whole. The wise council of Lord Vader when he said: "Do not be too proud of this technalogical terror that you've constructed." could well be applied here...... heh -W "Harry Krause" wrote in message ... K. Smith wrote: Matt Lang wrote: Whats your background and your background with motors if I may ask? There follows a seemingly endless regurgitation of KarenSmith b.s., but no answers to the specific questions posed to Ms. Smith, to wit: "Whats your background and your background with motors if I may ask?" The answers: No background whatsoever. No background with the motors. Zip, zilch, nothing, nada. |
Of course the same questions could be asked about harry WRT any topic and
the answer would be the same........except for pilfering union money....which he would be well qualified to answer. "Clams Canino" wrote in message ink.net... Unfortunately the lack of background does not stop her basic research from being more correct than not on a theoretical / technical level. The DFI motors do have some inherant lean burn issues. Issues that have been sucessfully "worked around" by throwing more electronics and technology at them, but still loom over the design concept as a whole. The wise council of Lord Vader when he said: "Do not be too proud of this technalogical terror that you've constructed." could well be applied here...... heh -W "Harry Krause" wrote in message ... K. Smith wrote: Matt Lang wrote: Whats your background and your background with motors if I may ask? There follows a seemingly endless regurgitation of KarenSmith b.s., but no answers to the specific questions posed to Ms. Smith, to wit: "Whats your background and your background with motors if I may ask?" The answers: No background whatsoever. No background with the motors. Zip, zilch, nothing, nada. |
"Harry Krause" wrote in message ... The fact that there are plenty of Yamaha and Merc DFIs around and running well, and that the Evinrude whatever the hell they called now selling well and running well speaks for itself. There are dozens and dozens and dozens of these engines powering the fishing boats leaving the marina where I keep Yo Ho, and I see these guys several times a week and talk to them. These high tech two strokes seem to be causing them no more trouble than the four cycle Yamahas and Suzukis of similar horsepower some of their friends have. Technology is evolving, eh? You build something as best you can, you test it, and if some units fail, you improve what you are doing and produced refined product, and that's how the process works. I would expect that next year's four cycle Yamaha 225 would be more refined than my 2003 model. And I haven't had any problems with my 2003 model. I'm not saying they can't be made to work. I'm saying they make me nervous as much as a small electronic failure can wipe out a powerhead. I'm more com fortable with them in your sal****er environment, where age won't be a factor in the long haul. :) -W |
[snip]
Whats your background and your background with motors if I may ask? When the DFI were released we (we is the blokes I work with) took a who exaclty is "we" ? [snip] Ficht failed spectacularly as predicted because the impact pressure rise was never going to supply enough pressure rise to give proper atomisation, coupled with the lean mixtures it had a serious failure rate & as I said was doomed from the beginning. Optimax faired a little better but still had the problem of low injection pressure (they use a normal injector pressure but unlike a normal injector into a vehicle manifold (which is usually below atmospheric pressure) they inject against the pressure of the output from the additional air pump, so the atomisation problem remains, as does the question of lean mixture heat buildup. These days optimax motors seem to work pretty well ? I havent heard recent failures.. Both technologies are by now totally discredited, Brunswick are clearly going 4 stroke throughout the range & Ficht brought OMC down, then Bomb (who have some proper engineers) got rid of it, now in a last desperate gasp E-tec will try to mitigate against the symptoms by using ever more heat resistant oil & pistons that will not "melt" till a higher temp:-) Sorry to smile but it's absurd!!! if petrol sees any temp around or above 250C it auto ignites (detonates), even the lowliest of aluminium is good to well over 600C. So their latest suck it & see try is as doomed as the original Fichts & for the exact same reasons; One hasnt heard of any bad news about HPDI ... doesnt this indicate there is no general problem and this can work fine? [snip] (v) It's long been known (mainly from aircraft engines, but also some attempts with car engines Chrysler, Honda & Mitsubishi) that engine can run on very lean mixtures, however the "abnormal" combustion leads to heat buildup in the chamber surfaces. Usually an engine running very lean will not detonate while still extremely lean (i.e. their latest sensor will not sense anything), but this doesn't stop the chamber surfaces getting overly hot. These days some car manufacturers have 4 stroke DFI motors which work well. Isnt that techinically the same as a 2 stroke DFI (in regards of the problems)? (vi) In an OB 2 stroke the head can be kept very cool being alloy & having an endless supply of cool water, but the piston/rings in a 2 stroke is almost totally uncooled. Once the piston temps gets over 250C (not very hot really) then auto ignition is a certainty but while lean probably no harm done, simply because there isn't enough fuel present. (vii) The trouble starts when the power is quickly increased above the lean burn mode, suddenly there is plenty of fuel available & this sudden excess fuel rather than cool the piston just auto ignites but now it will lead to full on detonation = more heat = more detonation etc etc bang... Do I read correctly that the dabgerous behaviour is: From idle to WOT? But lets say from 2000-3000 to WOT is no issue? [snip] (b) The piston aircraft engines are also run lean although never anything like as lean as Ficht & Optimax claim. Aircraft lean as the air density lowers with altitude so they're not really very lean at all & allowing that they're big slow turning essentially lazy engines, even so they still run the risk of having heat buildup in the chamber when operated too lean, so pilots are trained never to recover from lean cruising by just giving the engine full rich mixture & more throttle (exactly what happens when an OB is suddenly powered up after a long run in the lean mode). Pilots are trained to richen the mixture slowly as the power is slowly increased, this is to give the chamber temps time to normalise as the extra fuel is added; just in case:-) Now, what exactly is lean mode for a DFI outboard? Idle only or lets say below 3000 rpm? You are also welcome to email me. My email as posted is real. Sorry to be so long again, but this subject has been a war since 98 & it seems till Brunswick are all 4 stroke & E-tec has failed it will continue. No worries! I prefer detailed information and yes i run into some of the older "discussions" about the subject ;) Matt |
Matt Lang wrote:
[snip] Whats your background and your background with motors if I may ask? When the DFI were released we (we is the blokes I work with) took a who exaclty is "we" ? I have a small group of old blokes who do stuff, "we" develop all sorts of stuff, some for ourselves, some for others. They enjoy the tangles I get myself into in the NG but every single time so far they've been right on the money, even when "we" were definitely the odd ...... out in the early DFI days:-) [snip] Ficht failed spectacularly as predicted because the impact pressure rise was never going to supply enough pressure rise to give proper atomisation, coupled with the lean mixtures it had a serious failure rate & as I said was doomed from the beginning. Optimax faired a little better but still had the problem of low injection pressure (they use a normal injector pressure but unlike a normal injector into a vehicle manifold (which is usually below atmospheric pressure) they inject against the pressure of the output from the additional air pump, so the atomisation problem remains, as does the question of lean mixture heat buildup. These days optimax motors seem to work pretty well ? I havent heard recent failures.. I think that's probably right, however you don't see the endless purchasing spree of new ones like you did in the boom & Brunswick have all but given up on it & are going 4 stroke, not that the dealers trying to sell something will admit it;-) Both technologies are by now totally discredited, Brunswick are clearly going 4 stroke throughout the range & Ficht brought OMC down, then Bomb (who have some proper engineers) got rid of it, now in a last desperate gasp E-tec will try to mitigate against the symptoms by using ever more heat resistant oil & pistons that will not "melt" till a higher temp:-) Sorry to smile but it's absurd!!! if petrol sees any temp around or above 250C it auto ignites (detonates), even the lowliest of aluminium is good to well over 600C. So their latest suck it & see try is as doomed as the original Fichts & for the exact same reasons; One hasnt heard of any bad news about HPDI ... doesnt this indicate there is no general problem and this can work fine? No that's true & I comment about that to Tom, there are definite reasons they are more reliable (which tend to confirm the reasons why the others aren't), but it must cost Yamaha lots (800psi petrol???) so it seems they are also going 4 stroke. [snip] (v) It's long been known (mainly from aircraft engines, but also some attempts with car engines Chrysler, Honda & Mitsubishi) that engine can run on very lean mixtures, however the "abnormal" combustion leads to heat buildup in the chamber surfaces. Usually an engine running very lean will not detonate while still extremely lean (i.e. their latest sensor will not sense anything), but this doesn't stop the chamber surfaces getting overly hot. These days some car manufacturers have 4 stroke DFI motors which work well. Isnt that techinically the same as a 2 stroke DFI (in regards of the problems)? It is similar but as I said, other than dead idle, most of the time that a 4 stroke can risk running lean are times a boat motor just never sees. The comment about only half the ignition events is relevant to heat buildup also. (vi) In an OB 2 stroke the head can be kept very cool being alloy & having an endless supply of cool water, but the piston/rings in a 2 stroke is almost totally uncooled. Once the piston temps gets over 250C (not very hot really) then auto ignition is a certainty but while lean probably no harm done, simply because there isn't enough fuel present. (vii) The trouble starts when the power is quickly increased above the lean burn mode, suddenly there is plenty of fuel available & this sudden excess fuel rather than cool the piston just auto ignites but now it will lead to full on detonation = more heat = more detonation etc etc bang... Do I read correctly that the dabgerous behaviour is: From idle to WOT? But lets say from 2000-3000 to WOT is no issue? Yes after say 2000 (it varies) the engine is on normal mixtures so then if the oiling system is working as intended it should be as good as any non DFI 2 stroke. Opti does have a much better 7 into 7 (the extra is for the air pump) oiling system than Ficht's 1 into 6. [snip] (b) The piston aircraft engines are also run lean although never anything like as lean as Ficht & Optimax claim. Aircraft lean as the air density lowers with altitude so they're not really very lean at all & allowing that they're big slow turning essentially lazy engines, even so they still run the risk of having heat buildup in the chamber when operated too lean, so pilots are trained never to recover from lean cruising by just giving the engine full rich mixture & more throttle (exactly what happens when an OB is suddenly powered up after a long run in the lean mode). Pilots are trained to richen the mixture slowly as the power is slowly increased, this is to give the chamber temps time to normalise as the extra fuel is added; just in case:-) Now, what exactly is lean mode for a DFI outboard? Idle only or lets say below 3000 rpm? Idle up to about 1800 they put cyls back to full mixture mode at different times so you don't "feel" it as the boat accelerates. You are also welcome to email me. My email as posted is real. Sorry to be so long again, but this subject has been a war since 98 & it seems till Brunswick are all 4 stroke & E-tec has failed it will continue. No worries! I prefer detailed information and yes i run into some of the older "discussions" about the subject ;) Take care. K Matt |
Short Wave Sportfishing wrote:
On Mon, 22 Nov 2004 23:23:19 +1100, "K. Smith" wrote: ~~ snippage ~~ Sorry to be so long again, but this subject has been a war since 98 & it seems till Brunswick are all 4 stroke & E-tec has failed it will continue. Ah - now I understand the reasons for your antipathy towards FICHT. NIcely put by the way. I don't agree based on my own personal experience with FICHTS and what I know about them pre/post-OMC, but you have reasons and that's fine. It was interesting. :) I'm curious though. Your argument about diesel makes some sense - essentially, FICHT (and Etec for that matter) is diesel technology. Without going into a long treatise on the subject, I assume your contention is that FICHT is not a true two stroke and as such, problematic in the long run? No Ficht, Opti, E-tec, Yamaha dfi, are 2 strokes & as such if fed more normal mixtures "&" the piston's temp controlled then it would/should survive as well as other 2 strokes. The Yamahas have been interesting & somewhat more successful, they've had to resort to 800 psi & in one case 1000 psi petrol injection!!! so they can get enough atomisation to allow the lean mixtures to burn more predictably, also even they don't use mixtures as lean as Ficht & Opti. They randomly shut cyls down at low/med revs, so their aggregate EPA count still passes, but the pistons don't have to see such extremely lean mixtures/heat. It's probably relevant to mention & remember that right throughout the Ficht debacle & to a lesser extent Opti, they were making almost identical if not exact same engines, same parts, castings etc, Carbed Johnsons or EFI Mercs, yet only the Fichts or Opti DFIs failed..... why?? OMC were pushing the 2 strokes at 500cc per cyl that's getting to the limit, notwithstanding E-tec are going to try even bigger:-) (sorry that's a cheap shot Tom:-)) Again no secret knowledge involved here it's well known & understood that the bigger a petrol 2 strokes cyl gets the more difficulty it has dispersing heat out of the piston. All the high performance petrol 2 strokes have lots of small cyls. Even Clam's beloved old Mercs, which have to be the most successful 2 strokes ever built, had lots & lots of tiny pistons with very low cyl pressures. I know my view on this is against you Tom & I do apologise but as you can see I have copped an endless flogging mainly from Krause & the dealers, so when we were confirmed as right most of them just ran away leaving the people they'd conned holding the blown engine so to speak. K Later, Tom |
Harry Krause wrote:
Clams Canino wrote: Unfortunately the lack of background does not stop her basic research from being more correct than not on a theoretical / technical level. The DFI motors do have some inherant lean burn issues. Issues that have been sucessfully "worked around" by throwing more electronics and technology at them, but still loom over the design concept as a whole. The fact that there are plenty of Yamaha and Merc DFIs around and running well, and that the Evinrude whatever the hell they called now selling well and running well speaks for itself. There are dozens and dozens and dozens of these engines powering the fishing boats leaving the marina where I keep Yo Ho, and I see these guys several times a week and talk to them. These high tech two strokes seem to be causing them no more trouble than the four cycle Yamahas and Suzukis of similar horsepower some of their friends have. Are you just a simpleton Krause or can't you stop yourself lying?? It was your pension fund that backed Soros with unionists' retirement money!!! Have you not noticed that Ficht ****ed US$1.3 billion, that billion against the wall. This was during the biggest consumer spending spree in history!!! Dozens are OK so what?? 1 in 5 failed that was admitted & since then they've never admitted the failure rate again & they won't with this latest E-tec try. Technology is evolving, eh? You build something as best you can, you test it, and if some units fail, you improve what you are doing and produced refined product, and that's how the process works. This is technology that is known not to work, lean mixtures make heat then cause detonation. I don't expect you to have any understanding whatsoever but this "is" rocket science. If you have a burn in a closed chamber such that you cause a significant pressure rise, then it's very difficult to ensure that burn progresses in a predictable manner. If the mixture is too lean then ignition will be spasmodic & the flame front slow, if the mixture is too rich the burn will be at too low a temp, very dirty & use way too much fuel. Either side of those two, too lean or too rich & it just doesn't ignite at all. Even the shuttle only went closed loop very recently, before that it was all done on calculating the pressures, temps, etc etc & programing the oxygen & fuel amounts accordingly. They were & some still are experimenting to discover what everyone has known since the 1930s & they're using consumers money. I would expect that next year's four cycle Yamaha 225 would be more refined than my 2003 model. And I haven't had any problems with my 2003 model. Ah more lies you don't own a boat Krause & never have & never will, you are just a liar. K |
On Tue, 23 Nov 2004 19:53:06 +1100, "K. Smith"
wrote: ~~ snippage ~~ I know my view on this is against you Tom & I do apologise but as you can see I have copped an endless flogging mainly from Krause & the dealers, so when we were confirmed as right most of them just ran away leaving the people they'd conned holding the blown engine so to speak. I don't' have a problem with opposing viewpoints. I have a rather simple way of looking at things like this - to wit: If it works, it works. :) I will admit I came to FICHT late in the game and I will also admit that I literally had to be talked into purchasing one. And I will also admit that I had my share of problems with the OMC FICHT that is on my Ranger bay boat. However, Bombardier was more than willing to correct the problems without cost to me and once the engine was updated and made sound, I haven't had a problem with it. And the other two that I have, both Bombardier FICHTS have had zero problems. However, your discussion points make sense and I'm not discounting them. My experience has been positive and, for me that's is what is most important. To me, Mercury is the spawn of the devil and will remain that way until I can't get in a boat anymore. And it wasn't over their engines, it was over a $1,000 trolling motor that they refused to fix under warranty - sometimes the little things are bigger issues than the big things. :) Later, Tom |
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