V-Max 150 HPDI problems firing up

[scott_r]

Im not a mechanic by any means and am having some issues with this motor for the past month.
I have no problems starting my boat when I launch, I turn the key and it fires and runs great. My problem arrises when I hit my fishing spot, turn off the motor and fish for an hour or so and when decide its time to move. The motor turns over but takes along time to actually start. When the motor does start it sounds rough, puffs grey smoke for 30 secs and is fine. Ive found that if I turn the key over every 20 mins or so it starts fine but leave it much longer and it really struggles to fire up.
I changed my plugs with the proper plugs, Ive always got fresh fuel in it, oil level is great. I just put a brand new battery in it and am really not sure if this is a major fix or is it possible to do on your own? I have family members that are somewhat mechanical and if I knew what could be done I could see if they would do it. If not I guess its going to shop but Id like an idea of whats possibly wrong.

Cheers!!

 

[triumph190]

Re: V-Max 150 HPDI probelems firing up

Re: V-Max 150 HPDI probelems firing up

Check the primer bulb. Make sure it is firm. It won't be just real hard, but it should be some what firm.

When was the last time you replaced the bulb?

If that bulb isn't working correctly it will not keep the fuel system pressured up, which means gas will leak back into the tank after sitting. This will create a starvation of fuel at start-up, causing rough idle until the fuel pump can pick up fuel again.

 

[scott_r]

Re: V-Max 150 HPDI problems firing up

The primer bulb seems to be firm when I fire it up, but I'll take a better inspection when Im out next time. It would be great if it was that simple

 

[rodbolt]

Re: V-Max 150 HPDI problems firing up

trust me, its not going to be that simple.
that motor uses a Vapor Seporator Tank, VST.
the tank holds enough fuel on the engine to start and run several minutes without the fuel line attached.
I would start with a fuel rail presure check at the medium pressure valve,test for compression and spark. test the plug cap resistance and if all look good have a look at it while cranking with the laptop.
also test the lift pumps for leakage,if a diaphram is leaking it can create an excessivly rich fuel mix at hot restart.

 

[scott_r]

Re: V-Max 150 HPDI problems firing up

Im I looking at major coin to have this repaired? Ive been thinking about switching to a new 4 stroke, maybe even a new boat.

 

[triumph190]

Re: V-Max 150 HPDI problems firing up

May not always be simple, but sometimes simple keeps you from spending "major coin" in unnecessary repairs. As rodbolt said the vst should hold enough fuel to start the motor, although I have seen it not. I had a restriction in my fuel line coming fom the tank to the motor. The motor ran good a WOT, but when I would slow down to an idle all the gas in the vst would get consumed. This created a hard start up and rough idle. I would think a bad primer bulb that isn't keeping the fuel system in check could do the same thing.

Don't over look the small stuff...Just saying....

 

[rodbolt]

Re: V-Max 150 HPDI problems firing up

always look at the simple stuff first, however after priming the VST it will run ok until it runs dry, this isnt the complaint.
use a fuel system vacum gauge to measure fuel system vacum at the lowest pump intake. use the EFI fuel rail tester to check for medium pressure filter.
use a laptop or DVM to check the high pressure fuel.
at the high pressure fuel sensor you should read 5 volts orange to black and about 3v at idle between pink and orange.
pick up a copy of the tune-up spec guide and the service manual and you will see almost all of the sensors can be tested with a multi-meter.
the laptop is nice as it will give a better overall picture but its not always nessasry.
it will aide in not chasing ghosts though.