i have a jetski and a boat with an evinrude 115 hp outboard. can
they both use the same gas/oil mix? someone told me it should be
a pint to six gallons but i would rather mix a pint with 5
gallons because it's easier and to be on the safe side if that's
ok. is a pint to 5 gallons ok for both the jetski and the
evinrude?

thanks!

ted

ted@theted. wrote in message
...
i have a jetski and a boat with an evinrude 115 hp outboard. can
they both use the same gas/oil mix? someone told me it should be
a pint to six gallons but i would rather mix a pint with 5
gallons because it's easier and to be on the safe side if that's
ok. is a pint to 5 gallons ok for both the jetski and the
evinrude?

thanks!

ted



It's always wise to follow manufacturers recommendations. Deviating from
them could be trouble.


Wilbur Hubbard

Ted,
Adding lube oil to gasoline lowers the flash point of the fuel increasing the chance of detonation. Oil in the fuel is necessary
for these type of engines, but NEVER use more than the manufacturer's recommendation. Failure to follow this simple direction
could melt the pistons, the heads and effectively ruin the engine and I have seen this hundreds of times. I know this is counter
intuitive, hence the number of times this failure occurs.
Steve

ted@theted. wrote in message ...
i have a jetski and a boat with an evinrude 115 hp outboard. can
they both use the same gas/oil mix? someone told me it should be
a pint to six gallons but i would rather mix a pint with 5
gallons because it's easier and to be on the safe side if that's
ok. is a pint to 5 gallons ok for both the jetski and the
evinrude?

thanks!

ted

"Steve Lusardi" wrote in message
...
Ted,
Adding lube oil to gasoline lowers the flash point of the fuel increasing
the chance of detonation. Oil in the fuel is necessary for these type of
engines, but NEVER use more than the manufacturer's recommendation.
Failure to follow this simple direction could melt the pistons, the heads
and effectively ruin the engine and I have seen this hundreds of times. I
know this is counter intuitive, hence the number of times this failure
occurs.
Steve


Interesting. The Outboard Shop, the local evinrude/johnson dealer, gave me
the exact opposite recommendation. The question came up with my newer engine
which is designed to run on 100-1 mix. They told me it will run just fine
on the same stuff as my older engine, a 50-1 mix. They also cautioned me
that the least "too-little" mix , such as missing by a bit when filling from
a not-empty supply and having to guess at the right amount, could turn it
into an anchor. Failure to use enough deprives the engine of its
lubrication, and things seize up.

Further, my manuals for both engines show to use double the oil in severe
use conditions. I.e., in the newer one, 50-1, in the older one, 25-1. More
oil, at least as inferred from the manuals, assures that won't happen, even
if you overdo it.

I grant you that quadrupling the oil may have some deletorious effects, but
my common sense tells me that 16% more than specified as ADEQUATE should not
be a problem.

Also, I've never seen oil being more subject to explosion/flash than
gasoline. How does adding oil to fuel make it more volatile?

L8R

Skip

--
Morgan 461 #2
SV Flying Pig KI4MPC
See our galleries at www.justpickone.org/skip/gallery!
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"Believe me, my young friend, there is *nothing*-absolutely nothing-half so
much worth doing as simply messing, messing-about-in-boats; messing about in
boats-or *with* boats.
In or out of 'em, it doesn't matter. Nothing seems really to matter, that's
the charm of it.
Whether you get away, or whether you don't; whether you arrive at your
destination or whether you reach somewhere else, or whether you never get
anywhere at all, you're always busy, and you never do anything in
particular; and when you've done it there's always something else to do, and
you can do it if you like, but you'd much better not."

WARNING WARNING WARNING WARNING WARNING WARNING
WARNING WARNING WARNING WARNING WARNING WARNING
WARNING WARNING WARNING WARNING WARNING WARNING
WARNING WARNING WARNING WARNING WARNING WARNING

Interesting. *The Outboard Shop, the local evinrude/johnson dealer, gave me
the exact opposite recommendation.......

Fact: people forget 50% of what they hear immediatly.
In other words SKip you probablly heard, "bla bla bla recomend bla bla
evenrude bla..."

Further, my manuals for both engines show ........

Gaaaaa you have to comprehend also my selective reader.

I grant you that quadrupling the oil may have some deletorious effects, but
my common sense tells me........ should not be a problem.

Hey sikp have you been using your BrontoThesaurus again ? Please dont
use such big words as deletorius. They sont have a Salubrious effects
on my comprehension.

Also, I've never seen oil being more subject to explosion/flash than
gasoline.

How does adding oil to fuel make it more volatile?
L8R
Skip

Your comment and question shows a basic lack of fuel and combustion
concept understanding. Will those here more knowledgable please
inlighten SKip. Im off to watch the 30 foot 17 second swells hit the
jetty.

Robert RExroth
(Dell Tech Support-SLC, UT)
ADA

"Bob" wrote in message
...
WARNING WARNING WARNING WARNING WARNING WARNING
WARNING WARNING WARNING WARNING WARNING WARNING
WARNING WARNING WARNING WARNING WARNING WARNING
WARNING WARNING WARNING WARNING WARNING WARNING

Interesting. The Outboard Shop, the local evinrude/johnson dealer, gave me
the exact opposite recommendation.......

Fact: people forget 50% of what they hear immediatly.
In other words SKip you probablly heard, "bla bla bla recomend bla bla
evenrude bla..."

Further, my manuals for both engines show ........

Gaaaaa you have to comprehend also my selective reader.

I grant you that quadrupling the oil may have some deletorious effects,
but
my common sense tells me........ should not be a problem.

Hey sikp have you been using your BrontoThesaurus again ? Please dont
use such big words as deletorius. They sont have a Salubrious effects
on my comprehension.

Also, I've never seen oil being more subject to explosion/flash than
gasoline.

How does adding oil to fuel make it more volatile?
L8R
Skip

:: Your comment and question shows a basic lack of fuel and combustion
:: concept understanding. Will those here more knowledgable please
:: inlighten SKip. Im off to watch the 30 foot 17 second swells hit the
:: jetty.


I think Mr. Grundlach may be correct for once. Adding more oil to a given
amount of gasoline actually acts as an anti-knock ingredient. It lowers the
rate of speed at which the flame front propagates from source of ignition
(spark plug) to cylinder/piston surfaces.

It increases the duration of the burn and thus lowers the temperature of the
burn. Add too much oil and the motor will run as if the choke were on. I
don't know of any cases where piston damage from heat will result. The worst
that will happen is the works (piston rings piston crown) might become
gummed up, the exhaust port will become carboned up and exhaust gass passage
restricted and exhaust port opening retarded because the piston will have to
travel down several millimeters more before it reaches the exhaust port
opening. I have seen exhaust ports so carboned shut that one could barely
poke a finger through it. The engine would not rev up and it performed like
the choke was on all the time.

Too much oil is, indeed, a bad idea but not for the reasons you listed.

Wilbur Hubbard
(worked as a two-stroke mechanic for seven years and as a technical advisor
for a Japanese motorcycle company for seven years)

"I am Tosk" wrote in message
...
In article 29b625b4-9ffe-4736-b512-dff137d6aa81
@l8g2000yql.googlegroups.com, says...


haven't figured out what it was, but I shipped it:


Also, I've never seen oil being more subject to explosion/flash than
gasoline.

How does adding oil to fuel make it more volatile?
L8R
Skip

Your comment and question shows a basic lack of fuel and combustion
concept understanding.

Yeah, I gathered he isn't a internal combustion engineer so what's your
point? I worked on cars for a long time and really never thought about
ping as it relates to two stroke fuel/oil mix, I just mix it right and
with the octane we run, ping is not really an issue.. As to why the high
mixture and why it would cause ping, I have some ideas, but really, I
don't think it's all that important as long as I have a measuring cup...

That being said in my lawn equipment and boats I run regular fuel with
Spectro32:1 which is designed to run at that mixture in most two stroke
engines.. It's universal.


Will those here more knowledgable please
inlighten SKip.

Why, all he really needs is an answer to his question, he isn't asking
for a course?


This is a discussion group, isn't it? So why not discuss? The OP might learn
something.

Wilbur Hubbard

On Oct 25, 12:02*pm, ted@theted. wrote:
i have a jetski and a boat with an evinrude 115 hp outboard. can
they both use the same gas/oil mix? someone told me it should be
a pint to six gallons but i would rather mix a pint with 5
gallons because it's easier and to be on the safe side if that's
ok. is a pint to 5 gallons ok for both the jetski and the
evinrude?

thanks!

ted

I only have smaller 2 strokes and one jetski. The jetski mixes it's
self with a oil pump to the carbs. But I mix the same ratio for all
my small engines without any problems.

Lots of trimming

Also, I've never seen oil being more subject to explosion/flash than
gasoline. How does adding oil to fuel make it more volatile?

L8R

Skip

There are 2 parameters to consider these are the flash point - the min
temp at which it will ignite with a spark or flame etc.
This is typically -45F for petrol (gasoline) and +143F for diesel.
Hence as a boat fuel, diesel is a lot 'safer' than gasoline.

However there is also the autoignition temperature - this is the min
temp where the fuel will simply ignite without a spark or flame.
For Petrol this is 495F and for diesel 410F a fair bit cooler.

So too much oil could lower the auto ignition temp to a point where
pre-ignition happens - not good for your engine.

However I have no idea how much you need to add to cause this kind of
problem.

ted@theted. wrote in message
...
i have a jetski and a boat with an evinrude 115 hp outboard. can
they both use the same gas/oil mix? someone told me it should be
a pint to six gallons but i would rather mix a pint with 5
gallons because it's easier and to be on the safe side if that's
ok. is a pint to 5 gallons ok for both the jetski and the
evinrude?

thanks!

ted

I follow the manual recommendations.
i also dropped into the Vespa scooter store and bought the little plastic
measuring device.
It's great for a 50:1 mix. Saves guess work when out on the high seas.