J/30 Class Association Forums J/30 Forum The Boat, Sails and Equipment Will not start

Unbelievable the two biggest local regattas coming and the motor will not start. It was sucking half the fuel out of the filter on the engine now and then and stalling requiring a reprime and then it would be fine. Put new fuel pump on believing that it was the issue. Shut it off after one race and week later turns over runs for 3 seconds and dies. I changed the filter on the fuel water seperator (was very dirty and may have been the original issue), changed the filter on the motor added good fuel, pumped out bottom layer of fuel that was dirty in the tank, cleaned the injectors, checked the exhaust elbow. All seems to be fine. The engine sounds like it is trying to run when the starter is cranking it over but just dies when you stop. Checked that there was fuel coming out the high preasure lines at the injectors, how much preasure is supposed to be there? Played with the fuel shut off which seemed to end any good sound when cranking it over which sounds like it is not half on. Any ideas??

When you say you changed the fuel pump, was it the fuel lift pump on stbd side of engine, or the high pressure pump that feeds the injectors? My guess is that there is a problem somewhere between the inlet to the fuel filter to the inlet of the HP fuel pump, or bad compression (e.g. stuck valve or bad valve seat).

Try using a compression tester to make sure you have adequate pressure built up in the cylinders. Have the HP fuel pump bench tested at a diesel shop and while they're at it, check the individual cylinder timing. You should have very high pressure out of the HP fuel pump (don't have spec handy but I believe over 500psi). Have the injectors pop tested and see if the nozzles need replacement.

It was the lift pump. Took the valve cover off and valves seemed to work fine and do not know if the seat would be bad.
I have another mechanic coming and i will make sure he brings the tester. the preasure out of the HP pump is nowhere near that high, he put his finger over the line and it was squirting a bit past his finger. Injectors were checked by diesel shop. one time we were cranking it over and stopped he said he saw a spark come out of the intake. No fuel runs out of the return on the injectors when trying to bleed. Greg

ok - sounds like the HP fuel pump isn't doing its job, or is fuel starved. You're also on the right path with the compression check.

Just had my HP fuel pump rebuilt. My engine was blowing a lot of soot and hard to start. Its like a new motor! Ive been told that the new deisel fuel is hard on old fuel systems and to add a fuel additive to every tank.

Just heard from the Stairs Diesel and he does not believe that he has to replace all the components inside and thinks it might have been putting out enough fuel. He is replacing all gaskets and is going to bench test. I'll put it in tomorrow night and see what happens. Still have the mech coming friday morning so i'll cross my fingers. He did say they are very hard to bleed sometimes but we had solid fuel coming out the high preasure pipe without air. Maybe it is starving on the low preasure side??? Thanks stay tuned!

Pulled head and found split piston. Now have to pull motor and send to machine shop to find anything else gone. Damn motors

Sorry to hear that!

How much cranking did you do trying to get the motor started and did you shut off the raw water intake?

Cranking excessively with the intake open can pull water into the motor without enough pressure to eject it the through the exhaust and "hydrolock" the motor. Usually it will bend a connecting rod, but I suppose it could crack a piston.

Based on your description above, I was thinking fuel quality/delivery... Certainly not a
split piston.

Hope you get it sorted out quickly.

I tried it some when it was open but then shut it off to be safe. The motor ran for 5 seconds when we tried to get it started so it think the problem was there. No funny noises though!

There is no doubt you have air sucking somewhere, I recently had the same problem. I started with have the injectors re calibrated, then started at the fuel pump on the starboard side, one was tight, but just not tight enough. Then I moved to the injectors and bled them there. That was the problem. It can be quite frustrating, I know.
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