Bleeding fuel line

[david42]

I need to bleed my Yanmar because a certain marine engineer left the fuel tap turned off at the tank recently (I know I should have checked before I ran the engine but I assumed that he'd leave it 'repaired and ready to go' - my mistake).

My question is - do I just need to bleed it at the injector or do I need to bleed every pipe connection between the pump and the injector? It's a YSE12.

David

 

[Evadne]

I would bleed at every point where a bleed screw is fitted. Its probably quicker that way anyway. Not familiar with your model, but on my 1GM you would start with the secondary filter (in and out) filling with the lift pump lever, then the high pressure pump in and finally the injector in or hp pump out, which is the one where you tighten the nut while turning it over. I try and arrange a few disposable nappies under the engine to stop too much diesel finding its way into the bilges.

 

[david42]

Thanks Dave, that helps a lot. I esoecially, like the idea of the nappy.

David

 

[LORDNELSON]

I had this problem with my yanmar (3GM35 HM). I bled it at the diesel filter (did not bother with the separating filter because it is gravity fed and thus filled up). Then gave a long period push on the starter button. It fired on one or two cylinders and then after about 10 seconds the third cylinder kicked in and all was well.

 

[Spyro]

Good info HERE Remember with the YS series you have to have the throttle open to bleed the pipe between the injector pump and the injector. I had a similar situation once when I forgot to turn on the fuel stopcock. As usual the timing was perfect, right at the entrance to the marina. Managed to restart by only beeding as far as the bleed screw on the injector pump, started at the secondry fuel filter then the injector pump. Mine is a YSB with an electric lift pump so it makes it a bit easier.

 

[david42]

Thanks for the link - it looks really helpful.

 

[alant]

Don't forget to turn the seacock off if you are turning your engine over on the starter & no ignition - such as when bleeding the HP side to the injectors.
Otherwise you could fill the cylinders up with water from the exhaust, since the c/w pump will also be working, with no back pressure to blow the water outboard.
Turn back on when ignition achieved.

 

[gandy]

Does it do any harm cranking the engine over while it's bleeding through? I always hate that, it feels like I'm abusing the engine, and I worry about the injector pump running "dry". Is there anything to be worried about?

Tony S

 

[LORDNELSON]

I don't know. I did it some time ago and, to date, the engines OK. I reckon there is enough residual oil in the injector pump to tide it over the few seconds (the period cannot be long before the first bit of diesel arrives in the pump). I have been told by experienced marine engineers that you do not need to bleed at the injectors.