Any ideas, runs great then wont start

[dluck]

05 24V ran great then stopped to swim. Went to start but just turns over, the next day started just fine and ran it a couple minutes at the boat ramp while on the trailer with no issues. Any ideas on what is going on?

[Billua]

Simple things first, fuel filter been changed lately?

[TeamAllen]

First, welcome to the site! Post up a picture of our boat when you get a chance.

Where are you located? Myself and others have had this problem at Lake Powell.

[Pro-Fab]

was there water in you bilge at all? this has to be either elctrical or fuel related.

[ajholt7]

Vapor Lock. Pop the hatch and let it cool down.

[kbunch]

I have the same issue sometimes and agree vapor lock, I have even poured a bottle of water over the low pressure pump and could almost immediately hear the pump pressurize, I can predict when it WILL start, my question is does that imply a weak or soon to fail LP pump?

[ajholt7]

It just means your fuel line is getting hot turning the fuel into vapor and the pump can't prime. No problem with the pump itself.

[DieselPWR]

Same issue here and looks like either the low pressure or high pressure fuel pump. Also check the wiring going into the fuel pump. If any are loose and exposed that could be a simple fix.

[Tanner]

It's also your safety switch got jiggled. When trailering back home it got jiggled back into position.

Did you look and see if you had any spark?

[KonaKing]

05 24V ran great then stopped to swim. Went to start but just turns over, the next day started just fine and ran it a couple minutes at the boat ramp while on the trailer with no issues. Any ideas on what is going on?

Do you have the PCM motor?

Vapor lock is not generally associated with fuel injected motors, BUT with the PCM ZR6 the high pressure pump is outside of the fuel tank mounted to the side of the motor and feed by a low pressure fuel pump. The low pressure pump still needs to suck fuel from the tank which is at a lower elevation. I guess it is possible to have a vapor lock issue but not to likely. The High pressure pump has a large fuel bowl and should have all the fuel it needs to start and run again even hot.

Kind of sucks.

With a high pressure pump in the tank you could be 99% sure you are not having a vapor lock issue. Let us know which motor you have?

[sse01]

I am sure that I will get this wrong, but let me give it a shot! This is based on the Marine Power motor that is in our 2008. I was told that this is not common on most newer setups, however I have heard several instances of this recently.

Due to the increased safety devices for marine applications, there is a safety valve located on the exit of the fuel tank. It requires something like a 0.5 psi suction to overcome it. Between the high pressure fuel pump and the safety valve there is a low pressure pump that is intended to overcome the pressure needed for the safety valve. If the low pressure pump is not working, or is just not doing its job you can get vapor lock on the winter blends of fuel.

We always use our boat year around. This year we started experiencing troubles after running the boat until it was good and hot, then letting it sit for an hour or two. It would start, then sputter and die. This happened for months. I was opening the Shraeder valve on the fuel rail to release the air, then it would run just fine. Next winter I plan to explore the options to remedy this issue.

[jsz]

Same thing happenned to me several times recently and I thought it was vapor lock so we cooled the fuel rails, and blead the schrader valve. Sometimes it worked after a while, sometimes it did not. I was also told the anti-siphon valve at the tank might might be making the pump work work too hard to suck fuel. They replaced it and after it still didnt work, I remove it (no restriction at all now). Still didn't work.

We poored some fuel in the throttle body and it would start and run until the little bit of fuel ran out.

After replacing the external high pressure fuel pump it now runs fine.

IT WAS NOT VAPOR LOCK!!!!!!!

[jsz]

there is a safety valve located on the exit of the fuel tank. It requires something like a 0.5 psi suction to overcome it.

This is the anti-siphon valve.

[Jason B]

It's also your safety switch got jiggled. When trailering back home it got jiggled back into position.

Did you look and see if you had any spark?

The boat will not turn over at all when the key is engaged if the throttle is down or the safety switch is triggered.