hpdi outboard only run whilst cranking,,,,

[BastiaanMBok]

hi,helping out a friend of mine, he has a 250hpdi.
this is what's going on all of the sudden:
when he turns the keyswitch to start,,then engine cranks and starts.but as soon he lets key go back to on,,,the engine dies with it. will only run as long as you hold key in start position..(not good for starter.....)
is this a main relay problem or something else we have to look for??
cheers.
BMB

[99yam40]

Do you have the software and cable to hook up to a computer?
I would think that would be the best way to check things out.

You can check to see if the key switch is keeping Yellow wire hot in on position.
How about crank position sensor or what ever sensor it uses to tell ECU that motor is turning

[boats.net]

Check fuses on engine, main relay and fuel pump relay.

[BastiaanMBok]

well,there was more to it..engine had 0 compression on #4 cilinder.
today we replaced the piston,,a hole burned thru the crown of the piston.
replaced the injector as well,as this was causing the lean condition burning the hole in the piston.
further,no damage on clinder or engine..we just put it all together,and tomorrow going to start her up.
could it really be that this hole will cause the complete engine not to run???should run on 5 cilinders??or will the blowby cause so much turbulance that it will not run???
tomorrow will tell.
another thing,,this engine was submerged a couple of months ago,,but was taken apart&flushed&started within 5 hours from taking out of the water.
submerging was in salt water...all electrics had been serviced ,cleaned,fusebox,,etc..all electric plugs,starter,,everything.
if engine runs tomorrow,,I will post an A-OK,]
cheers
BMB

[99yam40]

No, one cylinder will not cause motor not to start

[BastiaanMBok]

another day of work: i had the yamaha diagnostics on it,,came out "irregular" fuel pressure.
replaced the high pressure fuel sensor,,and now all the diagnostic comes out OK.
look,,engine will start,but you really have to attempt about 8 times before it starts to run without shutting off.
its acting like it is way rich in fuel. it even throws out raw fuel out of the prop/exhaust..
so I directy did the injector diagnostics,,and I checked them one by one..they all give the even clicking sound..
so took off the VTS tank to get to the low pressure pumps to see if the diaphrams are not leaking thru the pulse hole.
all is good,,no problems there.
I suspect,,even that i can hear the injectors working,that they are leaking.
it is not normall for the engine to throw raw fuel out of the exhaust!!
as stated ,diagnostics all came out normall.
what else could there be beside leaking injectors??

[99yam40]

A motor that went under in salt could have any number of problems.
can you post what all the diagnostic read out showed?
Surely it gives fuel pressures along with lots of other info and not just abnormal or normal

Or are you just putting the wink-blinky on it instead of hooking up to a computer?

[BastiaanMBok]

nope,,no winky blinky.
I saved the file on my laptop with the yamaha 1.32 on it.
tomorrow morning I will copy it to my laptop and post it.
cheers
BMB