Hey, Yanmar Mechanics! Fuel Lift Pumps !

[Chief Engineer]

It seems that from the end of last season into this year I have seen a lot of leaking fuel lift pumps.....the Phillips screwws seem to loosen....anyone having the same problem?

I was thinking about cleaning them up a re-assembling with loc-tite?

Whaddya think?

[never monday]

Originally Posted by Chief Engineer

It seems that from the end of last season into this year I have seen a lot of leaking fuel lift pumps.....the Phillips screwws seem to loosen....anyone having the same problem?

I was thinking about cleaning them up a re-assembling with loc-tite?

Whaddya think?

that's not the Yanmar way

[DennisM]

I'm not a Yanmar mechanic, by any stretch of the imagination, but I'm replacing mine and keeping the leaky one as a backup. It might be just the fitting that is leaking, but with a 20-yr-old boat purchased last year with no maintenance records, I thought replacement would be prudent.

[Philsboat]

Loctite should work.I would use the medium strength 248 Loctite so the screws could be removed without heat.

Phil

[Chief Engineer]

Just curious.

Originally Posted by never monday

that's not the Yanmar way

[delmarrey]

I have a brand new Yanmar not even run yet. I've pulled the belt guard and the studs that hold it and those studs were loctite into place. So I would imagine/guess Yanmar does use loctite for a lot of it's applications.

The Japs do build pretty good motors but they don't think/proof sometimes on the finished product.

[Drumroll30]

I tightened the screws on mine when I discovered a leak, its still leaking so I'm replacing the pump.
I read an article lately in GOB about a 3GM30F with a lift pump that leaked after only 370 hours, the owner attributed the leak to using 30 % biodiesel fuel.

[never monday]

Originally Posted by Chief Engineer

Just curious.

yes sir, the Mikuini lift pumps are cheap

[DennisM]

Ugg. Thanks for the bad news, Drumroll. I have the 3GM30F.

[bill good]

I've got 2 X 1GMS & have been thinking of doing away with both the mech fuel pump & water pumps & replacing with external electric units. Has anyone done this??

Regards Bill

[never monday]

Originally Posted by bill good

I've got 2 X 1GMS & have been thinking of doing away with both the mech fuel pump & water pumps & replacing with external electric units. Has anyone done this??

Regards Bill

fuel pump is ok to do. Don't do the water pump. You need it's speed relational to engine RPM.

[Drumroll30]

Originally Posted by DennisM

Ugg. Thanks for the bad news, Drumroll. I have the 3GM30F.

According to the GOB article you should be fine if you don't use any biodiesel blend. The lift pump on my 2GM20F if now leaking and due for replacement but its given 23 seasons of service so I have nothing to complain about (except a sooty stern).

[Charlie]

Originally Posted by never monday

fuel pump is ok to do. Don't do the water pump. You need it's speed relational to engine RPM.

HI NM,
With the 4JH4E is it ok to use an electirc pump if the lift pump goes out. I am thinking of getting a spare lift pump but have a electric fuel pump laying around that I could plumb in easily enough. I know that you've mentioned it before but can you also answer this question. Should the electric pump go before or after the Racor?

[never monday]

after the racor. and you should be fine Charlie

[byteshredder]

It appears that I also have some loose screws...on my fuel lift pump. My buddy and I purchased a 30' sailboat with a Yanmar 2GM20F. As we were tracking down the source of the diesel smell, we determined that at least one source is the diaphragm of the fuel lift pump. With the heat exchange directly on top of this pump we can't tighten the screws directly. We will have to remove the pump from the block. My question is what sacrificial parts will we need on hand to put the pump back in service once we've tightened things down? Replacing the gasket between the pump and the block seems appropriate. What about the fittings that connect the fuel lines to the pump? What about the diaphragm itself. The engine is 20 years old and although some parts seem to be newer, the lift pump appears to be original. The boat is used for coastal weekend cruising. The engine runs fine and start fine. The boat is in FL.