In line fuel filter leak

[ken003]

There is a small inline filter at the inlet to the fuel lift pump on the M35B engine.  The original filter leaked slightly from day one.  It took me a while to find it.  The seam in the casing of the filter looked to be bad and my broker said they would check into it.  While installing the new one I figured out what had happened.  I tightened it too tight and the filter casing rubbed up against the bottom of the pump.  I did not notice this at first and tightened a couple more turns.  This broke the seal of that seam in the filter and thus the leaking.  The original installer must have done the same thing.  Has anyone else had this problem?  Do I simply not tighten it as much.  Can I put teflon tape on this joint?  I thought I saw somewhere in the manual not to use tape on these joints close to the pump and injectors.

Thanks,
Ken 

[Ron Hill]

Ken : Most inline filters have one or more barbs on each end to help seal.  Instead of a hose clamp with a screw they have a small spring wire "clamps" for narrow spots.  I wouldn't think you should need any filler like teflon tape if the filter is made for that size fuel line.   

[ken003]

Ron:  Here is a picture.  I should have put it on the first time.  These are all threaded fittings.  The filter screws horizontally into the elbow in the bottom of the pump.  You can see the filter touching the pump above the elbow connection.  I would think that many M35B engines are the same way so there must be a simple explanation for installing this correctly.  When I get back to the boat I will use teflon tape and screw the filter in until almost touching the pump body.  Unless someone else has a better idea.


Ken

[Steve Hansen]

I'm just curious as to why the in line would be needed if the racor which filters to 2 microns is upstream of this? The M25XP has no arrangement like this. Steve

[Ed Shankle]

Ken,
I'd suggest using plumber's thread compound. Blue stuff, that doesn't dry out and harden. It may have been used on your fuel tank fittings, if you check them out. I think Ron may have referenced it it one of the posts regarding the fuel tank fittings.
My observation is that this stuff makes a better seal. Teflon it good for easy of screwing two pieces together.

Ed

[Ron Hill]

Ken : Thanks for the picture, it explained all.
What I'd do in go to and automotive parts store and get some Number 2 Permatex (non harding).  Put it on the threads or joints of any part that's around oil/fuel and you'll have a good seal.   

[Fred Jackson]

I had a similar leak on my M35B when it was brand new.  The mechanic who repaired it under warranty said that the filter casing is very thin and can not take any significant twisting moment.  My casing was cracked.  He used teflon tape when he installed the replacement and I have had no problems in 80 hours of run time.  I carry two of those critters aboard at all times as spares.

Fred J.
Amante Catalina 36 #2209

[Ted Pounds]

I'm with Steve Hansen.  Why can't you just ditch this little filter?  It seems like it's a solution without a problem.  Just a thought...

[Stu Jackson]

I concur with Ted, and haven't understood the purpose of this filter.

If, however, you want to keep it, why not just install a short piece of hose from the bottom of the fitting that it is currently hitting to move it away from the obstruction.

[Roc]

My M35B didn't come with this filter.  My friend with a C350 (two year old boat, same engine), has this in-line filter.  Don't know why some have it and some don't.  You would think Universal would be consistent.  I think the Racor, at 2 microns should be sufficient.

[John Sheehan]

This is the service bulletin from Westerbeke that should explain the filter and also raise some more questions.

SERVICE BULLETIN #238
DATE: 28 FEBRUARY 2003
MODEL: ALL MODELS-DIESEL PROPULSION ANDGENERATORS AND GASOLINE
GENERATORS
SUBJECT: FUEL PUMP INLET FIL TER PN#048076
FILTER IS BEING ATTACHED TO THE INLET OF "ALL" FUEL PUMPS ON BOTH DIESEL
PROPULSION AND GENERATORS AND GASOLINE GENERATOR MODELS BEGINNING THE
LATTER PART OF MARCH 2003. (MANUFACTURING DATE CODE E303)
THIS IS BEING DONE TO ENSURE THAT THE FUEL ENTERING THE FUEL PUMP IS BEING
PROPERLY FILTERED TO PROTECT THE FUEL PUMP FROM CONTAMINATION.
THE INLET OPENING OF THE FILTER IS THE SAME AS THE INLET OPENING IN THE FUEL
PUMP (1/8 X 27 NPTF). THIS SHOULD POSE NO PROBLEMS WITH EXISTING FUEL LINE
CONNECTIONS.
THIS FILTER "MUST" BE USED. IF THE FILTER IS REMOVED WARRANTY ON THE FUEL
PUMP IS VOID.
THE FILTER SHOULD BE REPLACED ON A NEWLY COMMISSIONED UNIT AFTER THE FIRST
50 HOURS OF OPERATION. THEN EVERY 250 HOUR, ANUALLY OR AS NEEDED.
WESTERBEKE CORPORATION STILL RECOMMENDS THE INSTALLATION OF A PRIMARY
FILTER/WATER SEPARATOR BETWEEN THE FUEL TANK AND THE ENGINE. THE FILTER
USED IN THIS SHOULD NOT HAVE A MICRON RATING SMALLER THAN 10 MICRONS.

[Stu Jackson]

Thanks, John

Anybody have any more input on this unusual issue?

Those of us with the OLD engines didn't seem to have these kind of issues, since the 85 filters we put in between the  tank and the engines seemed to be enough.   

[ken003]

It seems strange that westerbeke wants to insure the fuel is filtered properly.  This inline filter is only for 80 microns.

[Ron Hill]

Ken : I'd go with the inline filter, especially if your engine is still under warranty !!!!!!!!
As far as teflon tape goes, it might be OK.  I've found that diesel mechanics use the product that easier for them to carry, which may NOT be the best item for sealing.  Permatex #2 is for seals and gaskets in an"oily" environment.  Read the label!!   

[Ted Pounds]

It only says the warranty on the FUEL PUMP is void, not the whole engine.  I think I'd ditch it anyway.  Sounds like it's so poorly made and prone to leak that it's a fire hazard!  FWIW...