Yanmar GM Series Fuel Lift Pump Refurb

[Slowboat35]

Has anyone managed to rebuild one of these?
The workshop manual confidently instructs to 'replace packings' but omits any useful mention of the diaphragm.
Are parts available, haven't managed to find any so far - or is it the usual Yanmar scam to make you buy a whole new unit for a king's ransom?

 

[VicS]

Has anyone managed to rebuild one of these?
The workshop manual confidently instructs to 'replace packings' but omits any useful mention of the diaphragm.
Are parts available, haven't managed to find any so far - or is it the usual Yanmar scam to make you buy a whole new unit for a king's ransom?

£45 from Parts4engines

 

[Bilgediver]

£45 from Parts4engines

there will also be valve components. Enjoy the search

 

[RichardS]

there will also be valve components. Enjoy the search

Surely all the components come with the new pump?

Richard

 

[vas]

what are the symptoms?
have opened up mine 3 times the last couple of months on the (possibly wrong) assumptions it was leaking some air in the system (tank lower than pump) and was not pumping properly.
Easy to open, cleaned everything carefully, dismantled the two tiny valves and cleaned them (looking for any debris that would keep them half open).
Eventually problem was traced to yet once more leaking vent hole on the bolt on filter.
does leak diesel back though, fitted a non-return valve before the lift pump.

V.

 

[Slowboat35]

Vic, thanks for that address, I had no idea Yanmar bits were available that cheap. The other supplier I used charged £48 for a piston ring "kit" for a 3GM that turned out to be for one piston only which I thought exceedingly steep, as well as verging on dishonest wording and still isn't even genuine Yanmar!! Fifty quid for one ring-set! Staggering rip-off! Your people charge the same for a real 3 piston kit. There really are some robbers out there!

vas, the punp wasn't showing any sign of sucking against a finger as the manual suggests it should. I dismantled it, cleaned it up inside and on reassembly saw the gasket on the engine case was interfering with the lever. I trimmed this away with a Stanley knife and now it sucks as it should.

Thanks all!