Yanmar 2gm fuel lift pump leak

[pateco]

I am getting a fuel leak on my Yanmar 2gm engine, and it looks to be coming from the area of the fuel lift pump. It is definitely leaking red, off road diesel fuel. My spill absorbing pad in the engine bilge is bright red. LOL

I searched the forum, and found this closed thread https://forums.sailboatowners.com/index.php?posts/1065602/, and it seams to be the solution to my problem. However googling for the gasket, diaphragm, and banjo washers gave me no good results. Does anyone know the part numbers for these, or have a link to where to buy them?

Also, do I need to drain the engine oil before removing the pump?

 

[Sailm8]

Check here for a lead: https://sbo.sailboatowners.com/dl/downloads.php

 

[pateco]

Check here for a lead: https://sbo.sailboatowners.com/dl/downloads.php

Thanks Sailm8,
I found the instructions on how to take it out on Pages 150-152 of the Yanmar GM Shop Manual Part 2, and it is a strait forward procedure. The Diaphram may not be servicable sinceYanmar says "Internal parts for the fuel transfer pump are not available. Replace a defective pump; do not attempt to overhaul it." however the pump still works so I don't think it is a diaphragm leak.

This being said, I still cant find part numbers for the banjo washers and gasket.

 

[Ralph Johnstone]

Also, do I need to drain the engine oil before removing the pump?

You're safe with the oil level as the fuel pump is WAY above the level in the sump.

I eventually replaced my engine lift pump with an electric lift pump placed back in an open and convenient location. Just seemed to be chasing banjo fitting copper crush gaskets every few years. The very first fuel leak I discovered had soaked the rear starboard motor mount and that's where the battle began.

If you're looking for pump parts, you'll have to find a Yanmar dealer in your own area. Can you spell M O N O P O L Y ? ? ?

And yes, the pumps are not repairable. Another reason for looking at an electric lift pump and cleaning up the whole mess.

 

[pateco]

Found the gaskets:
Gasket-Lift Pump-1Gm(2-20F)3Gm Product Code:Y 121520-01851

 

[pateco]

Another reason for looking at an electric lift pump and cleaning up the whole mess.

What did you do with the original pump? just remove it and block off the opening in the block?

 

[pateco]

I may have found a washer solution in another thread; Fixed my Yanmar 3gm30 with Harley Davidson parts, but how many should I order to replace all I have and still have spares?

SKU: HD-41756-08 $1.16/each

 

[kloudie1]

Couple of things.. The top/bottom halves of the lift pump can become loose allowing a leak.. you can tighten the cover screws with a right angle screwdriver.. next are the banjo washers.. I whole heartedly recommend the washers with the rubber inserts.. They are officially called "Dowty" washers..
Check this out.. https://forums.sailboatowners.com/i...-30-copper-crush-washer-size-injector.164190/

 

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[Ralph Johnstone]

What did you do with the original pump? just remove it and block off the opening in the block?

That was it exactly. Used a piece of 3/16" plate cut to the shape of the old lift pump base and used a pump base gasket to seal the old hole.

Here is the new setup back in an area which is wide open for maintenance .................

Now to deal with the leaking copper crush washers on the secondary pump .

 

[pateco]

Have any of you tried re-annealing and reusing the copper crush washers? How much torque should be used on the banjo bolts to generate a seal without damaging the bolts?

 

[rhwins]

Access to starboard side of engine is limited by the wall of the head. Thinking of cutting an access opening to service the fuel pump, but the electric pump is a fix I used on old English sports cars and they last for many years. Electric feed from ignition or a separate switch?

 

[dandelang]

I had a stubborn fuel leak from the lift pump. I purchased a new pump but did not want to tackle the job. I read about replacing the copper washers so I finally replaced it all (using the bathroom vanity slider mirror vertically for better visualization!). Tough job! I could not get any fuel out at the bleed screw after at least 100 pumps on the pump lever. Finally, with the bleed screw loose, I ran the engine for 5 seconds. Nothing. Again for 5 seconds..I got fuel! She runs fine, no fuel leak, but now I have an OIL LEAK Seems to be from the dipstick. So frustrated! Where did I go wrong?

 

[mermike]

Probably misaligned the gasket under the pump. Darn near impossible to line them up when you have limited access. Replacing the bolts with studs helps. Or go the electric pump route.

 

[dandelang]

Wouldn't it be leaking fuel, if the gasket was an issue? I'm not leaking any fuel, just oil pushing past the dipstick.

 

[Ralph Johnstone]

I'm not leaking any fuel, just oil pushing past the dipstick.

OUCH. Don't meant to piss on your corn flakes this early in the morning but it sounds like you "may" have excessive crankcase pressure to push oil out and around the dipstick seal.

I would suggest checking the breather and its tubing to make sure it has a clear path back to the combustion air inlet.

The original heading for this post was for a Yanmar 2GM. However, don't you have a Universal for which the above insert won't help you ? Check the archives for your Universal manual.

 

[dandelang]

You nailed it the first time! Leaking around the gasket where the fuel pump attaches to the engine. My work scenario, do it, then do it again the right way!

 

[Ralph Johnstone]

My work scenario, do it, then do it again the right way!

Some people here prescribe to the work motto : do it, then do it again, and do it, then do it again, and do it, then do it again, and do it, then do it again .......................... ad infinitum.

 

[dandelang]

I hope I don't ever have to do that job again. Gasket got mangled. I had a spare and I am no longer leaking fuel or oil. Thanks so much for the prompt, ACCURATE reply. That was a big help! Thanks again!