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New style (spin on) Raycor (diesel) fuel filters
My old Raycor with its replaceable element has failed. What I see now
in the catalogs are units with spin on filters. With the old style, when you removed the old filter, the fuel stayed in the bowl. Put in a new filter, top up, and close it. The old filter had almost no fuel in it, and it took almost nothing to top up. How do the new units work? I'm imagining a procedure similar to an oil filter replacement, except that after I remove the old, I have to fill the new one with fuel. -- |
New style (spin on) Raycor (diesel) fuel filters
these are really nice, I always try to drain the bowl......
http://www.defender.com/cgi-bin/Web_...ta log=301012 Marc Auslander wrote in message news:... My old Raycor with its replaceable element has failed. What I see now in the catalogs are units with spin on filters. With the old style, when you removed the old filter, the fuel stayed in the bowl. Put in a new filter, top up, and close it. The old filter had almost no fuel in it, and it took almost nothing to top up. How do the new units work? I'm imagining a procedure similar to an oil filter replacement, except that after I remove the old, I have to fill the new one with fuel. -- |
New style (spin on) Raycor (diesel) fuel filters
these are really nice, I always try to drain the bowl......
I've had several recommendations for the Raycor 500 series. Thanks. As a primary filter (my engine has a built in fuel filter) to you use the 2 micron or the 10 micron element? I would think that given the size of my engine (Yanmar 2GM) I should just use 2 micron even though its the primary filter. -- |
New style (spin on) Raycor (diesel) fuel filters
Several years ago I repowered my prev boat with a Yanmar 3GM. A few
weeks later I received a notice from Mack Boring that use of a filter smaller than 30 micron places stress on the lift pump and that use of such a filter would void the warranty. I started using a 30 micro (red) element and changed the on-engine filter more often. This spring while returning from the Bahamas, we lost our engine (Perkins) and had to be towed the last few miles to Palm Beach. Turns out that the lift pump failed. Mechanic at Ribovitch-Spencer said that it is true that too small of a filter can cause lift pump failure. He recommended at 30 micron as well along with changing the on-engine filter regularly. Doug s/v Callista "Marc Auslander" wrote in message ... these are really nice, I always try to drain the bowl...... I've had several recommendations for the Raycor 500 series. Thanks. As a primary filter (my engine has a built in fuel filter) to you use the 2 micron or the 10 micron element? I would think that given the size of my engine (Yanmar 2GM) I should just use 2 micron even though its the primary filter. -- |
New style (spin on) Raycor (diesel) fuel filters
On my Pathfinder, I use a coarse (30 micron) filter as the first in line
filter from the tank (I always forget if that is primary or secondary). The next one is finer (a Bosch as per specs). The coarse filter does the job in getting out the big chunks and the finer filter is working of the finer grit. That way the filters should fill up about evenly -- Dennis Gibbons S/V Dark Lady CN35-207 email: dennis dash gibbons at worldnet dot att dot net "Doug Dotson" wrote in message ... Several years ago I repowered my prev boat with a Yanmar 3GM. A few weeks later I received a notice from Mack Boring that use of a filter smaller than 30 micron places stress on the lift pump and that use of such a filter would void the warranty. I started using a 30 micro (red) element and changed the on-engine filter more often. This spring while returning from the Bahamas, we lost our engine (Perkins) and had to be towed the last few miles to Palm Beach. Turns out that the lift pump failed. Mechanic at Ribovitch-Spencer said that it is true that too small of a filter can cause lift pump failure. He recommended at 30 micron as well along with changing the on-engine filter regularly. Doug s/v Callista "Marc Auslander" wrote in message ... these are really nice, I always try to drain the bowl...... I've had several recommendations for the Raycor 500 series. Thanks. As a primary filter (my engine has a built in fuel filter) to you use the 2 micron or the 10 micron element? I would think that given the size of my engine (Yanmar 2GM) I should just use 2 micron even though its the primary filter. -- |
New style (spin on) Raycor (diesel) fuel filters
That's right... just like an oil filter change. Be sure to get the special
wrench to remove the bowl from the old cartridge. You can do it with a couple of oil filter wrenches, but you'll bust a lot of knuckles and cuss a lot. The thing you have to think about is the cost. The spin-on elements are a lot more expensive than the cartridges. I have a Racor 900 as my first filter, but replaced that dual cartridge filter setup on the Lehman with a spin-on Racor. Since I use 2 micron in both, the final filter shouldn't have to be changed nearly as much, and I just HATED changing out those dual cartridges. I could NEVER get them on without leaking for at least two tries. -- Keith __ You start with a bag full of luck and an empty bag of experience. The trick is to fill the bag of experience before you empty the bag of luck. "Roy G. Biv" wrote in message om... these are really nice, I always try to drain the bowl...... http://www.defender.com/cgi-bin/Web_...ta log=301012 Marc Auslander wrote in message news:... My old Raycor with its replaceable element has failed. What I see now in the catalogs are units with spin on filters. With the old style, when you removed the old filter, the fuel stayed in the bowl. Put in a new filter, top up, and close it. The old filter had almost no fuel in it, and it took almost nothing to top up. How do the new units work? I'm imagining a procedure similar to an oil filter replacement, except that after I remove the old, I have to fill the new one with fuel. -- |
New style (spin on) Raycor (diesel) fuel filters
I use 2 micron in the primary and final. Since my fuel is clean (polishing
system) I want the primary to catch pretty much everything, since it's easier to change. This is for a Lehman 135. -- Keith __ Before Xerox, five carbons were the maximum extension of anybody's ego "Marc Auslander" wrote in message ... these are really nice, I always try to drain the bowl...... I've had several recommendations for the Raycor 500 series. Thanks. As a primary filter (my engine has a built in fuel filter) to you use the 2 micron or the 10 micron element? I would think that given the size of my engine (Yanmar 2GM) I should just use 2 micron even though its the primary filter. -- |
New style (spin on) Raycor (diesel) fuel filters
"Keith" wrote in message ...
I use 2 micron in the primary and final. Since my fuel is clean (polishing system) I want the primary to catch pretty much everything, since it's easier to change. This is for a Lehman 135. -- Keith __ Before Xerox, five carbons were the maximum extension of anybody's ego "Marc Auslander" wrote in message ... these are really nice, I always try to drain the bowl...... I've had several recommendations for the Raycor 500 series. Thanks. As a primary filter (my engine has a built in fuel filter) to you use the 2 micron or the 10 micron element? I would think that given the size of my engine (Yanmar 2GM) I should just use 2 micron even though its the primary filter. -- Always use the filter type the manufactorer reccomends. Polishing (BS in my opinion) or not, a filter causes restriction. You need fuel flow in a diesel, if you restrict the flow by going to a tighter filter, your asking for trouble unless you go to a larger filter that will flow the correct amount of fuel. If your not getting the proper amount of fuel flow not only will you cause wear on the pump, you will also get reduced power output. This is simply one of those cases where more is not better. |
New style (spin on) Raycor (diesel) fuel filters
Get the type (filter head casting) with the integral hand operated
priming pump (plunger); or, see below. How do the new units work? I'm imagining a procedure similar to an oil filter replacement, except that after I remove the old, I have to fill the new one with fuel. Install a 12v fuel pump between the tank and the first filter. Energize the pump with a switch. When installing new filters, etc. turn on the pump and then sequentially bleed all the filters, lift pump, final filter. Also serves as a 'back-up' lift pump. When not energized the integral valves in the pump will allow the fuel delivery system to operate just as before. Actually lift pumps on engines shouldn't be located where they are, they should be at the tank. Then you have a positive pressure system that cant suck air from leaky joints, etc. Additionally a positive pressure system will vastly increase the service life of the filters! |
New style (spin on) Raycor (diesel) fuel filters
Sorry but these 'mechanics' have it all and entirely WRONG !!!!!
Too small a filter means NOT too small a retention rating but too small a SURFACE AREA of the filter. What kills the lift (or any other) pump is particulate and continually working against a high differential pressure caused by either too small or too plugged a filter. If you have a dirty tank or a tank without a recirculation filter use: 30uM followed by 10uM followed by 2uM ... the 2uM can be the 'guard' filter between lift and high pressure pumps. If you double the surface area, the differential pressure needed to operate the filter at the design flow will be HALF .... and the service life (to plugging) will be approximately *FOUR* times longer; plus, the particles will be stopped on the filter media! The higher the differential pressure the greater the possibility to extrude soft and deformable particulate through the filter media.... only to plug a finer rated filter / orfice, etc. downstream. Of course you MUST in all cases monitor the performance of such filters with pressure/vacuum gauges ... and check them periodically to develop a plot of lifetime vs. time/gallons in service and WHEN to change them. Bigger filters will SAVE you $$$$ and 'sudden' headaches, are more cost effective and "removal efficient" than changing out teeny (and just as expensive) filters on a 'seasonal' basis. Change when the pressure gauges tell you to change them, install at least the next LARGER *surface area* filter recommended, ............ instead of waiting for the filters to plug ... when the weather is very rough/severe, you NEED the engine to keep moving for safety, you and your crew are seasick/tired/terrorized/etc.... and on top of this you have to go below and change the filters then bleed the system - all the while you're projectile-puking great lumps into the smelly bilge. That's not my idea of fun! Better yet is to install a recirculation filter with an integral gravity water knock-out pot ... then you only need a regularly sized final filter, will have no bacteria/water/particulate/sudden power loss/etc./etc./etc. You can wire such a system so that the recirc. pump operates any time the engine is operating. Hope this helps. |
New style (spin on) Raycor (diesel) fuel filters
I think this is what I said. Too small a filter (pore size) causes
stress on the lift pump. This is what the mechanic said and also what the memo from Yanmar stated. A clogged filter will always place stress on the pump. The case was told of was using a 2u filter in a Raycor 500. I'm installing a permanent polishing system as well. Doug "RichH" wrote in message ... Sorry but these 'mechanics' have it all and entirely WRONG !!!!! Too small a filter means NOT too small a retention rating but too small a SURFACE AREA of the filter. What kills the lift (or any other) pump is particulate and continually working against a high differential pressure caused by either too small or too plugged a filter. If you have a dirty tank or a tank without a recirculation filter use: 30uM followed by 10uM followed by 2uM ... the 2uM can be the 'guard' filter between lift and high pressure pumps. If you double the surface area, the differential pressure needed to operate the filter at the design flow will be HALF .... and the service life (to plugging) will be approximately *FOUR* times longer; plus, the particles will be stopped on the filter media! The higher the differential pressure the greater the possibility to extrude soft and deformable particulate through the filter media.... only to plug a finer rated filter / orfice, etc. downstream. Of course you MUST in all cases monitor the performance of such filters with pressure/vacuum gauges ... and check them periodically to develop a plot of lifetime vs. time/gallons in service and WHEN to change them. Bigger filters will SAVE you $$$$ and 'sudden' headaches, are more cost effective and "removal efficient" than changing out teeny (and just as expensive) filters on a 'seasonal' basis. Change when the pressure gauges tell you to change them, install at least the next LARGER *surface area* filter recommended, ............ instead of waiting for the filters to plug ... when the weather is very rough/severe, you NEED the engine to keep moving for safety, you and your crew are seasick/tired/terrorized/etc.... and on top of this you have to go below and change the filters then bleed the system - all the while you're projectile-puking great lumps into the smelly bilge. That's not my idea of fun! Better yet is to install a recirculation filter with an integral gravity water knock-out pot ... then you only need a regularly sized final filter, will have no bacteria/water/particulate/sudden power loss/etc./etc./etc. You can wire such a system so that the recirc. pump operates any time the engine is operating. Hope this helps. |
New style (spin on) Raycor (diesel) fuel filters
If a 0.000000000002 micrometer rated filter has enough surface area it
will operate with LESS differential pressure than a small surface area filter with 3 METERS pore size. This is a vacuum pump ... meaning that it only has to deliver 15 psi motive pressure plus about 2-3 feet of static head. A small dog can **** harder than that. The service advisory simply admits that Yanmar has a WEAK pump!!!!!!! A pump that cant run against a 'dead-head'is cheap, ill designed, etc. A clogged filter will always place stress on the pump. A filter begins to become 'clogged' when approx 85% of its 'dirt capacity' is used, less than that the pressure drop is linear, after that it rapidly accelerates the rate of 'clogging' (becomes exponential) ..... thats why you NEED a gauge to monitor it. |
New style (spin on) Raycor (diesel) fuel filters
I'm installing a gauge as well, readable from the steering station. When
I owned the Yanmar, I chose to abide by what the manufacturer said rather than risk my warranty. I'm funny like that. New system is going to take into account all the good advise you and other have offered. I'm not going to get caught with a dead engine again. DOug ps. Get a bigger dog :) "RichH" wrote in message ... If a 0.000000000002 micrometer rated filter has enough surface area it will operate with LESS differential pressure than a small surface area filter with 3 METERS pore size. This is a vacuum pump ... meaning that it only has to deliver 15 psi motive pressure plus about 2-3 feet of static head. A small dog can **** harder than that. The service advisory simply admits that Yanmar has a WEAK pump!!!!!!! A pump that cant run against a 'dead-head'is cheap, ill designed, etc. A clogged filter will always place stress on the pump. A filter begins to become 'clogged' when approx 85% of its 'dirt capacity' is used, less than that the pressure drop is linear, after that it rapidly accelerates the rate of 'clogging' (becomes exponential) ..... thats why you NEED a gauge to monitor it. |
New style (spin on) Raycor (diesel) fuel filters
Subject: New style (spin on) Raycor (diesel) fuel filters
From: "Doug Dotson" I'm installing a gauge as well, readable from the steering station. When I owned the Yanmar, I chose to abide by what the manufacturer said rather than risk my warranty. I'm funny like that. New system is going to take into account all the good advise you and other have offered. I'm not going to get caught with a dead engine again. If you're going to all that trouble you might as well install the water probes and alarms while you're at it. Capt. bill |
New style (spin on) Raycor (diesel) fuel filters
Good idea.
"LaBomba182" wrote in message ... Subject: New style (spin on) Raycor (diesel) fuel filters From: "Doug Dotson" I'm installing a gauge as well, readable from the steering station. When I owned the Yanmar, I chose to abide by what the manufacturer said rather than risk my warranty. I'm funny like that. New system is going to take into account all the good advise you and other have offered. I'm not going to get caught with a dead engine again. If you're going to all that trouble you might as well install the water probes and alarms while you're at it. Capt. bill |
New style (spin on) Raycor (diesel) fuel filters
Uhmmm....
RichH wrote: If a 0.000000000002 micrometer rated filter has enough surface area it will operate with LESS differential pressure than a small surface area filter with 3 METERS pore size. Hardly! You need to study the issue of "bubble point" before making this type of assertion. Basically, surface tension becomes the dominant factor in backpressure when porosity is decreased to sub-micron levels. In GENERAL, one can overcome delta-p issues due to lower average porosity by increasing surface area, but certainly not allways. Oh, and "small surface area" and "3 METERS" together do not make a filter. It's a "HOLE". A BIG hole :-) Keith Hughes |
New style (spin on) Raycor (diesel) fuel filters
Here's my experience with vacuum gages. I have a Lehman 135. The primary
filter is a Racor 900 with 2 micron filters. The final is now a Racor Spin-on with a 2 micron cartridge. I always check the vacuum gage on the Racor underway, and it NEVER shows any vacuum. I even let that filter go too long and pulled it out looking like it was coated with black jelly... still no vacuum or effect on the engine. The filter is just HUGE compared to what the Lehman sips... about 4 gallons/hr. consumed, 1.5 GPH or so returned. I even took the vacuum gage off awhile back to make sure it was working; it was fine. If you have a filter that's really big compared to what your engine uses, you'll almost never show any vacuum. -- Keith __ It's only unethical if you get caught. "Doug Dotson" wrote in message ... I'm installing a gauge as well, readable from the steering station. When I owned the Yanmar, I chose to abide by what the manufacturer said rather than risk my warranty. I'm funny like that. New system is going to take into account all the good advise you and other have offered. I'm not going to get caught with a dead engine again. DOug ps. Get a bigger dog :) "RichH" wrote in message ... If a 0.000000000002 micrometer rated filter has enough surface area it will operate with LESS differential pressure than a small surface area filter with 3 METERS pore size. This is a vacuum pump ... meaning that it only has to deliver 15 psi motive pressure plus about 2-3 feet of static head. A small dog can **** harder than that. The service advisory simply admits that Yanmar has a WEAK pump!!!!!!! A pump that cant run against a 'dead-head'is cheap, ill designed, etc. A clogged filter will always place stress on the pump. A filter begins to become 'clogged' when approx 85% of its 'dirt capacity' is used, less than that the pressure drop is linear, after that it rapidly accelerates the rate of 'clogging' (becomes exponential) ..... thats why you NEED a gauge to monitor it. |
New style (spin on) Raycor (diesel) fuel filters
ummmmmmm yourself
Bubble point is related to retention efficiency ---- ONLY. If your were filtering a 60/40 mixture of isopropyl alcohol and water your statement would have (some) validity .... but ONLY if your were using uniform porosity polymeric *membranes* at retention levels below 0,45uM. It is a mathematical/physical impossibility to consider 'bubble point' for such fixed media (fiberous) and comparatively HUGE retention sizes. If you know what a bubble pointg is, then you also know that such fixed fibrous media has inconsistant porosity and permeability - ie. a 2uM media will have 'pores' approaching 50 or 100uM!!! Bubble point is simply not applicable. For yourself I respectfully suggest that you look up the filtration regimes as defined by the ASTM "OSU F-1 protocols" Operating differential pressure is SOLEY due to the absolute viscosity of the fluid!!!! Bubble point is a nondestructive CORELATION or a bacterial (specified test organism) challenge (or latex spheres) ... to a plugging situation using specific test organisms on MEMBRAWES. Oil filters use a fiberous media ... where bubble point is totally nonapplicable: 1. non uniform media, 2. retention matrix larger than 1uM. Tell me where on this planet that one can do a 'bubble point' (or forward flow diffusion) on the media type used in fuel oil filters? - is fiberous and non-uniform in permeability; and thus, are unable to be tested via bubble point as the contact wetting angle of surface tension vs. the media is nonuniform. Bubble point is ONLY perfomed on MEMBRANES of ?0.45uM used in filtration .... not on fiberous nonuniform porosity media. Differential pressue of a CLEAN filter is SOLELY due to the absolute viscosity (viscous shear) of the fluid being filtered. Surface tension is irrelevent with respect to viscous shear/?P. Changing the surface tension (wetting angles) will ONLY affect the *retention* ability under varying intrusion pressures ... ie:. modifying the van der walls absorbtive attraction at the BET surface of the media or membrane. Differential pressure affects the internal velocity of the fluid THROUGH filter media/membrane AND those media with high ?P will have/approach insufficient contact or residence time for absorbtion mechanism of capture; thus, leaving only mechanical means of 'captu'seiving', direct interception and inertial impaction. You can matematically predict by the (area1/area2)E1.66 = (velocity2/velocity1)E1.66 = ((Q/deltaP1)/(Q/deltaP2))E1.66 ...as a LIFE performance predictor (the exponential varies between 1 for high viscosity non-newtonian fludis to approx 1.666 for newtonian fluids.... no surface tension/wetting angles involved. |
New style (spin on) Raycor (diesel) fuel filters
sorry, the greek delta was ASCII transmitted as a: ? therefore the "?P" characters in the previous posting should be read as "delta P" |
New style (spin on) Raycor (diesel) fuel filters
jscanlon wrote in message
-- Always use the filter type the manufactorer reccomends. Polishing (BS in my opinion) no bs at all... my permanently installed independent polishing system draws about 5 gallons (100 gallon tank) every 6.5 minutes through a racor 1000 with 2 micron (can switch to racor 900 when 1000's vacuum increases) the engine has a racor 500 with 10 micron , then racor 500 with 2 micron, then the perkins 4-108 engine mounted filter. as rich points out the 1000 elements aren't much more expensive than the 500 elements, don't let the 500/1000 designations throw you, the surface area of the 1000 is MUCH greater than twice the surface area of the 500...... |
New style (spin on) Raycor (diesel) fuel filters
If your polishing system is 'off line' ... not a part of the normal fuel
distribution and return loop the following will exponentially improve the retention ability and 'speed of recovery' if you happen to get a load a cruddy fuel or the sea state breaks a slug of particale loose from the tank walls, etc.: Dont use 2uM filters in the loop! .... increase the nominal retention rating to 10 or 15uM and the resultant final particle distribution *in the tank* will be essentially zero and accomplish this level FASTER. ... here's why: Fibrous media filters have retention capability at essentially ALL particle size levels. A 15uM fuel filter will remove approx 85 to 95% of of 15uM particles in a one single pass of the fluid through it, at 10uM 50%, at 5uM perhaps 30%, at 2uM maybe 15%. A 15uM filter will have approx 4 to 5 times the flow rate capacity (gallons per minute per psid) of a 2uM filter ... meaning that the 15uM filter will cause less work for the pump and overall flow will be FASTER. A 2uM filter will deposit 2uM particles primarily on the surface of the media, a larger retention media will capture 2uM particles down deep in the media (for *more* capacity of small particles) Since a polishing system is a closed recirculation system you are constantly filtering the same fluid over and over and over, each time the fluid passes through the filter it leaves a few percent of smaller particles behind in the filter, since a larger retention filter has better flow characteristics the pump will push through MORE fluid per minute and have less amperage draw. When using a 2uM filter, the fluid returned during recirculation to the tank is again mixed with particle/debris laden fluid. A larger retention filter will do the same job, to the same level of particles in the tank ..... and do it faster because the larger retention filter has less resistance to flow. With less resistance to flow a larger retention filter will have less probability of extruding and releasing SOFT/DEFORMABLE particles at it approaches differential pressures that would 'clog' a filter. Another benefit - If for example you have a crud contamination hanging on the walls of the tank and the sea state causes the attached particles/crud to break free and enter the fluid, the larger retention filter (because of its less resistance to flow) will recover the tank back to an acceptable particle distribution (particle recovery) FASTER than a smaller retention filter. Same story when taking onboard a load of fuel that is contaminated. Recirculation filtration is exponentially faster, more efficient, and vastly more cost effective than single pass filtration. Use the largest filter retention possible (~10-20uM) to effect the fastest tank turn-over... the tank will after a few turn-overs be to the same level of residence particles. For the mathematicians, what is happening is an exponential decay of resident particles *in the tank*; since the larger retention filter (even with less efficiency with respect to the 'target retention') is Faster because the exponential decay 'in the tank' is faster. If you have time to burn, take ANY filter (includes compressed pubic hair), recirculate for looooong times and you will have essentially ZERO particles in the tank. Typically in industry a recirc. filter is sized about 5 to 10 times the size of the target residual retention. hope this helps. Roy G. Biv wrote: jscanlon wrote in message no bs at all... my permanently installed independent polishing system draws about 5 gallons (100 gallon tank) every 6.5 minutes through a racor 1000 with 2 micron (can switch to racor 900 when 1000's vacuum increases) the engine has a racor 500 with 10 micron , then racor 500 with 2 micron, then the perkins 4-108 engine mounted filter. as rich points out the 1000 elements aren't much more expensive than the 500 elements, don't let the 500/1000 designations throw you, the surface area of the 1000 is MUCH greater than twice the surface area of the 500...... |
New style (spin on) Raycor (diesel) fuel filters
RichH wrote in message ...
Get the type (filter head casting) with the integral hand operated priming pump (plunger); or, see below. How do the new units work? I'm imagining a procedure similar to an oil filter replacement, except that after I remove the old, I have to fill the new one with fuel. Install a 12v fuel pump between the tank and the first filter. Energize the pump with a switch. When installing new filters, etc. turn on the pump and then sequentially bleed all the filters, lift pump, final filter. Also serves as a 'back-up' lift pump. When not energized the integral valves in the pump will allow the fuel delivery system to operate just as before. Actually lift pumps on engines shouldn't be located where they are, they should be at the tank. Then you have a positive pressure system that cant suck air from leaky joints, etc. Additionally a positive pressure system will vastly increase the service life of the filters! The only bad side to the positive pressure is if you have a leak. I was on a large boat once that had a leak by the injection pump. The boat was running fine, but I make it a habit to take a look at the engines every so many hours. So I go down for a peek, find about 3 to 4 inches of diesel in the bilge. The dangerous part, some of the fuel was in the form of a fine mist, not a good thing, thank God for water cooled turbo's. My point is, I think I'd rather live with the problem of finding an air leak. |
New style (spin on) Raycor (diesel) fuel filters
Thanks Rich,
I've been doing filter validation for 20 years, so yes, I know of what you speak. Now, show me either of: A spun depth filter with "a 0.000000000002 micrometer" absolute porosity, OR ANY spun filter with any absolute porosity rating. The point is, you were wildly exaggerating, and I was pointing that out. If you *could* create a filter of the listed porosity, the surface tension alone would create such a high pressure you'd never get any flow at all. As you obviously know. Oh, and you might want to reconsider statements about "differential pressure is SOLEY due to the absolute viscosity" of the liquid. Never had the fun of filtering thixotropic products eh? Keith Hughes RichH wrote: ummmmmmm yourself Bubble point is related to retention efficiency ---- ONLY. If your were filtering a 60/40 mixture of isopropyl alcohol and water your statement would have (some) validity .... but ONLY if your were using uniform porosity polymeric *membranes* at retention levels below 0,45uM. It is a mathematical/physical impossibility to consider 'bubble point' for such fixed media (fiberous) and comparatively HUGE retention sizes. If you know what a bubble pointg is, then you also know that such fixed fibrous media has inconsistant porosity and permeability - ie. a 2uM media will have 'pores' approaching 50 or 100uM!!! Bubble point is simply not applicable. For yourself I respectfully suggest that you look up the filtration regimes as defined by the ASTM "OSU F-1 protocols" Operating differential pressure is SOLEY due to the absolute viscosity of the fluid!!!! Bubble point is a nondestructive CORELATION or a bacterial (specified test organism) challenge (or latex spheres) ... to a plugging situation using specific test organisms on MEMBRAWES. Oil filters use a fiberous media ... where bubble point is totally nonapplicable: 1. non uniform media, 2. retention matrix larger than 1uM. Tell me where on this planet that one can do a 'bubble point' (or forward flow diffusion) on the media type used in fuel oil filters? - is fiberous and non-uniform in permeability; and thus, are unable to be tested via bubble point as the contact wetting angle of surface tension vs. the media is nonuniform. Bubble point is ONLY perfomed on MEMBRANES of ?0.45uM used in filtration .... not on fiberous nonuniform porosity media. Differential pressue of a CLEAN filter is SOLELY due to the absolute viscosity (viscous shear) of the fluid being filtered. Surface tension is irrelevent with respect to viscous shear/?P. Changing the surface tension (wetting angles) will ONLY affect the *retention* ability under varying intrusion pressures ... ie:. modifying the van der walls absorbtive attraction at the BET surface of the media or membrane. Differential pressure affects the internal velocity of the fluid THROUGH filter media/membrane AND those media with high ?P will have/approach insufficient contact or residence time for absorbtion mechanism of capture; thus, leaving only mechanical means of 'captu'seiving', direct interception and inertial impaction. You can matematically predict by the (area1/area2)E1.66 = (velocity2/velocity1)E1.66 = ((Q/deltaP1)/(Q/deltaP2))E1.66 ...as a LIFE performance predictor (the exponential varies between 1 for high viscosity non-newtonian fludis to approx 1.666 for newtonian fluids.... no surface tension/wetting angles involved. |
New style (spin on) Raycor (diesel) fuel filters
Thanks for those insights Rich, I guess the key is how much the
different uM ratings load the pump and change its volume/time. I have used different micron rated filters and never noticed a perceptible change in the flow rate (5 gallons in 6.5 minute is pretty slow)... RichH wrote in message news:... If your polishing system is 'off line' ... not a part of the normal fuel distribution and return loop the following will exponentially improve the retention ability and 'speed of recovery' if you happen to get a load a cruddy fuel or the sea state breaks a slug of particale loose from the tank walls, etc.: Dont use 2uM filters in the loop! .... increase the nominal retention rating to 10 or 15uM and the resultant final particle distribution *in the tank* will be essentially zero and accomplish this level FASTER. ... here's why: Fibrous media filters have retention capability at essentially ALL particle size levels. A 15uM fuel filter will remove approx 85 to 95% of of 15uM particles in a one single pass of the fluid through it, at 10uM 50%, at 5uM perhaps 30%, at 2uM maybe 15%. A 15uM filter will have approx 4 to 5 times the flow rate capacity (gallons per minute per psid) of a 2uM filter ... meaning that the 15uM filter will cause less work for the pump and overall flow will be FASTER. A 2uM filter will deposit 2uM particles primarily on the surface of the media, a larger retention media will capture 2uM particles down deep in the media (for *more* capacity of small particles) Since a polishing system is a closed recirculation system you are constantly filtering the same fluid over and over and over, each time the fluid passes through the filter it leaves a few percent of smaller particles behind in the filter, since a larger retention filter has better flow characteristics the pump will push through MORE fluid per minute and have less amperage draw. When using a 2uM filter, the fluid returned during recirculation to the tank is again mixed with particle/debris laden fluid. A larger retention filter will do the same job, to the same level of particles in the tank .... and do it faster because the larger retention filter has less resistance to flow. With less resistance to flow a larger retention filter will have less probability of extruding and releasing SOFT/DEFORMABLE particles at it approaches differential pressures that would 'clog' a filter. Another benefit - If for example you have a crud contamination hanging on the walls of the tank and the sea state causes the attached particles/crud to break free and enter the fluid, the larger retention filter (because of its less resistance to flow) will recover the tank back to an acceptable particle distribution (particle recovery) FASTER than a smaller retention filter. Same story when taking onboard a load of fuel that is contaminated. Recirculation filtration is exponentially faster, more efficient, and vastly more cost effective than single pass filtration. Use the largest filter retention possible (~10-20uM) to effect the fastest tank turn-over... the tank will after a few turn-overs be to the same level of residence particles. For the mathematicians, what is happening is an exponential decay of resident particles *in the tank*; since the larger retention filter (even with less efficiency with respect to the 'target retention') is Faster because the exponential decay 'in the tank' is faster. If you have time to burn, take ANY filter (includes compressed pubic hair), recirculate for looooong times and you will have essentially ZERO particles in the tank. Typically in industry a recirc. filter is sized about 5 to 10 times the size of the target residual retention. hope this helps. Roy G. Biv wrote: jscanlon wrote in message no bs at all... my permanently installed independent polishing system draws about 5 gallons (100 gallon tank) every 6.5 minutes through a racor 1000 with 2 micron (can switch to racor 900 when 1000's vacuum increases) the engine has a racor 500 with 10 micron , then racor 500 with 2 micron, then the perkins 4-108 engine mounted filter. as rich points out the 1000 elements aren't much more expensive than the 500 elements, don't let the 500/1000 designations throw you, the surface area of the 1000 is MUCH greater than twice the surface area of the 500...... |
New style (spin on) Raycor (diesel) fuel filters
You're welcome, but this is not a place to show off that one can properly open the correct box of filters. Lets get back to helping simple boating folks to keep the crud and critters out of their fuel and diesel engines in the simplest and most efficient, less costly way possible, please. As applied to simple plain vanilla fuel oil systems .... Ill stand pat and depend on 35+ years of experience in engineering, design, tech support, marketing, consulting, in high tech filtration and separation technology, ... with the 'major' players and with the up-and-comers (& some down and goners). For the last time .................. Now, show me either of: A spun depth filter with "a 0.000000000002 micrometer" absolute porosity, OR cant fathom hyperbole, and simplified exaggeration to attempt to explain to the non-technical. ANY spun filter with any absolute porosity rating. Pall Profile, Osmonics Selex, are a few of the more common examples .... last time I looked these were absolute to a beta 5000 efficiency which would equate to a approx 1X10E7 / sq. cm. titre reduction (LRV) for "up to" but not quite sterilizing requirements. Ya gotta remember before macro-foam polymer membranes the industry used such things as potassium titanate fibers, asbestos, etc. to effect single pass 'absolute' level filtration. The point is, you were wildly exaggerating, No, I was being "mister wizard" to the Saturday morning science class. If you *could* create a filter of the listed porosity, the surface tension alone would create such a high pressure you'd never get any flow at all. As you obviously know. News to me, you must have had a 'public school education' ;-) ... 1. absolute visosity is the prime factor of viscous shear hence differential pressure ... Ill stand on that statement, unless they've recently changed physical chemistry, chemical engineering, and the laws of fluid dynamics. Never had the fun of filtering thixotropic products eh? Biological gels or protenaceous concentrations? .... about once every 3-4 months but with tangential filtration levels in the nanometer or 10000 Dalton range. I actually prefer viscoelastics. If you want to take this offline, my professional fees are $175/hr. |
New style (spin on) Raycor (diesel) fuel filters
Roy G. Biv wrote: Thanks for those insights Rich, I guess the key is how much the different uM ratings load the pump and change its volume/time. I have used different micron rated filters and never noticed a perceptible change in the flow rate (5 gallons in 6.5 minute is pretty slow)... There is a 'ratings game' with such filters. Firstly, 'paper' filter media cant be made that accurately, plus the cellulose fibers used are relatively thick in comparison to the 'pores'. So, in especially the larger retention ratings you probably wont see much difference in flow performance. With respect to cheap filters, you usually get what you pay for. :-) |
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