Vortec 6.0 trouble starting????

[loudelectronics]

Ok so heres the deal. I know I have posted this issue compiled with a different issue all together however I have not heard any ideas on this.

I use the boat in the morning for a couple hours and it will start fine and run fine. When done the boat will sit at the dock for a few hours in the sun and heat. If we go us the boat after it sits it will not start at all. So after trying to start it for 5 minutes or so, if you just let it sit for 5-10 minutes it will turn over like nothing was ever wrong. The boat runs fine after this as well. I can actually predict when this is going to happen too. So when I know we are going to take it out I will go try to start it and let it run for the 10 seconds before it dies, crank it a few times, let it sit and start it again so we are good to go. This really has me boggled. Not sure why it does this.

ANy ideas?

[dogbert]

I'd say vapor-lock, but I know you're in Canada so heat shouldn't really be an issue for you. That said, you might want to check your fuel cooler to make sure you are getting good circulation through there (maybe some debris from a fragged impeller?). Try running your blower for a while before you start it or open the engine hatch to see if that makes a difference.

[loudelectronics]

Yes opening the hatch does seem to work.

Vapor Lock? What is this? I hav heard of vapor lock or gassification of fuel in lines of carbed vehicles but not EFI.

Where is the fuel cooler?

The temp has been about 85-90 deg lately. Does not do it on cooler days though and I do not think my blower works. Yeah I bought a good one! But I love it so much so I deal.

[chpthril]

It can happen on EFI engines for 2 reasons, or combo of both. Hi under-hood temps can boil fuel, even under pressure. The other is if the fuel pressure is able to bleed off while engine is off, the fuel can boil off and turn to gas (as in vapor, not liquid). Just like coolant, when under pressure, it's boiling point is raised.

[loudelectronics]

Any permanent fixes for this. Never had this issue with boats before.

[chpthril]

It's my understanding that there is a mod to the fuel system/cooler for this, unless it's just a part failur allowing the pressure to bleed off, something like the regulator , injector, or fuel pump.

[dogbert]

If opening the hatch helps, just run the blower for a little while to cool off the engine compartment. That's the easiest fix.

[mtnsmith]

Call Dom 888-517-3178, or pm him at FIC, he is the dealer on here that runs a 6.0 that he did the modification on. I believe he is the one that discovered this fix. Good luck.