7.4 GSI not starting after running.

[NorCal226]

I am inquiring about a fix for what I believe is vapor lock issue. I have found plenty of posts both for VP and Mercury 7.4 having starting issues after stopping which is what I am experiencing. This gives you a very unnecessary feeling when your way out on a lake with no one around. This last weekend we were out in the middle of lake Almanor in Nor Cal watching the sunset, no one around and when we went to leave the boat would not start. Finally got it started about 20 minuets later after leaving the hatch open. My wife was not very happy and I admit I had thoughts of spending the night on the lake, not fun. Everyone says to run the blower continuously and open the hatch to release the heat and that does work but I believe that should not have to be the norm as it is a P.I.T.A. and I am looking for a fix. Here are my boat specs and what I have done attempting to correct this issue. I have a 2000 226 with a 7.4GSI DP serial #4012022446. Brand new crate motor installed by prior owner (all receipts in hand) in 2019 and I purchased the boat in 2020 which had less than 100 hrs on the new mtr. I have installed a new paint free fuel cell from Man Cave, new fuel regulator on the fuel rail. Installed an additional lift pump between the tank and the fuel cell. Replaced the distributor cap, rotor, control module, distribution module within the distributer and a new coil. New water pump impeller and thermostat, boat runs at 150* .
Note: Boat starts every time and runs excellent and strong. We can stop in a cove for awhile and maybe the the boat will start and we can cruise off, we stop again and maybe this time it will not start. The motor turns over great, there is spark at the distributer and the fuel cell is just warm to the touch, not hot. If I wait for 20 to 30 minuets with the hatch open and exhaust fan running the motor will eventually start again. I have run out of ideas how to fix this issue and as I have said I have found that this is not uncommon when searching on line but never a fix. Has anyone else fixed this issue?

[Big Block Power]

Are you using non ethanol gas?

[NorCal226]

Yes and I was wondering if that might be the issue.

[Big Block Power]

Also let the engine idle for a few minutes before you shut it down to get cooler gas in the lines before shut down.

[Kate]

What BB said. Idle to anchor, like you idle to dock.

Also, what are you doing with the throttle at start? A common mistake is over-priming.

[bruceb58]

What BB said. Idle to anchor, like you idle to dock.

Also, what are you doing with the throttle at start? A common mistake is over-priming.

How do you overprime a fuel injected engine?

[NorCal226]

Not sure what you mean by over-priming. With the EFI I turn the key, wait for the fuel pumps to stop then turn key to start. No throttle is given, I have the controls it the locked upright position. I do idle the engine before shutting down as I have read that procedure on other post's.
Update; Friday I went and filled the boat with ethanol free gas to dilute the 1/4 tank I had left. Didn't have issues on the lake but the outdoor temp was below 100. Unless there is other recommendations I will wait and see if the fuel is the culprit as we have a few more hot days still coming here in northern CA.

[jhnmdahl]

Yes and I was wondering if that might be the issue.

I've always heard ethanol gas was more prone to vapor lock because the ethanol vaporized more easily than the rest of the gas. "Winter blend" gasoline with butane in it has similar issues, but shouldn't likely find its way into a boat.

[Kate]

"How do you overprime a fuel injected engine?"

Throttle use while starting a FI engine can throw off the fuel-air ratio, thus causing flooding. Not sure it's precise to call that "over-priming."

[NorCal226]

Update: We have been out three times since filling up with ethanal free gas and we have not had an issue since. Need a few more trips to mentally not think about this happening but the boat is running great. Talk about pain at the pump the 92 octane ethanal free here in CA is $9 a gallon! So when they do not add a foreign substance to gas they charge more, go figure it would be like diesel.

[Krob1114]

Update: We have been out three times since filling up with ethanal free gas and we have not had an issue since. Need a few more trips to mentally not think about this happening but the boat is running great. Talk about pain at the pump the 92 octane ethanal free here in CA is $9 a gallon! So when they do not add a foreign substance to gas they charge more, go figure it would be like diesel.

First time we got stuck on the water boat had been running fine. After towing in and almost heading home, local mechanic took off the fuel filter and dumped it. You could actually see that the gas and ethanol had separated. New filter and all was fine. We use only non-ethanol gas now.

[AsLan7]

.
Appreciate the update.