Starting problem on Yanmar YSM8G

Polarsailor

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My friends Yanmar refuses to start, No previous history of starting issues until now.

There is fuel in the tank, the engine stop is fully in, and I have chased the fuel through as far as the high pressure pump, no air appears to be present and the bleed screws let diesel out. However if I release the HP pipe from the pump to the injector (single cylinder) nothing comes out. I am presuming the pump is knackered anyone else have any other thoughts? Am I missing another possibility here?

Any help gratefully recieved.
 
When you look for pump delivery, is the speed control lever at maximum?
IIRC, the pump on these engines is very simple and could be stripped by a DIY owner, but perhaps best to have a manual. There is a fuel delivey ball valve that might be the culprit, but that's only a guess.
 
Thanks guys, no stop solonoid fitted so not that. The throttle was on about 1/2 so should have been plenty to get fuel out of the pump. I suspect it probably is the pumpo but thanks for the comments...
 
Hi-
My last boat has a YSM 8 .... noisy aren't they? But so frugal...

I may have a pdf manual

Even though they are very robust and agricultural, diy work on the hp pump, governor or injector may result in a large paper weight.

Could you/your friend give some more info?
when did it last run?
How was it starting then?
Was the idling noticeably slower/stalling in idle?
Has any work been done to it recently esp fuel system?
Tried Easy Start? (yes.. I know almost as dangerous as an 'best anchor' thread!

Mine had a head gasket fault, I convinced myself it was fuel. (not to say it's the case here)

Nick
 
My friends Yanmar refuses to start, No previous history of starting issues until now.

There is fuel in the tank, the engine stop is fully in, and I have chased the fuel through as far as the high pressure pump, no air appears to be present and the bleed screws let diesel out. However if I release the HP pipe from the pump to the injector (single cylinder) nothing comes out. I am presuming the pump is knackered anyone else have any other thoughts? Am I missing another possibility here?

Any help gratefully recieved.

I take it that the engine is being turned over with the hp pipe disconnected.

dont exepct to see giant squirts of fuel. After all you say it is economical.
 
Is the throttle actually moving the lever on the governor/delivery lever at the pump?
I have some scanned copies of the pump assembly from the manual. PM your e-mail if you want them.
 
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