1997 5.7 won't start when warmed up

[toyterrific]

Thought my engine dying at low idle may be a carb problem so I installed a fully-reman'd 2-barrel mercarb and new plugs and still dies.
Also had trouble in past re-starting when warmed up. It now has to sit about an hour to start again.
Had to shut off to gas up at Marina. Of course, it would not start. Towed back to slip, trying to start a few times on way. Once up on lift it finally fired, (as if mocking me).
Thought about vapor lock but why would that show up now? Was not a problem past two seasons.
Any ideas?:huh:

Thanks.

 

[tdschafer]

I'm not sure what is causing your problem but, vapor lock can occur due to the gas tank vent getting clogged. Either the screen corroded over or I have heard of mud wasps making a nest in the vent line. Did any gas overspill out of the vent when you gassed up?


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Todd

 

[dwna1a]

When was the last time you changed the filter, including the one at the carb? Also which carb did you put on the boat? Could it just be flooding easily?

I would check the vent first

 

[SeaRide]

Toy,

Shoot CliffA a PM. He just resolved the same issue you are experiencing.

 

[CliffA]

Thought my engine dying at low idle may be a carb problem so I installed a fully-reman'd 2-barrel mercarb and new plugs and still dies.
Also had trouble in past re-starting when warmed up. It now has to sit about an hour to start again.
Had to shut off to gas up at Marina. Of course, it would not start. Towed back to slip, trying to start a few times on way. Once up on lift it finally fired, (as if mocking me).
Thought about vapor lock but why would that show up now? Was not a problem past two seasons.
Any ideas?:huh:

Thanks.

maybe you can find some answers in this thread.....i spent two years off and on chasing a similar problem but finally resolved the problem...

http://clubsearay.com/showthread.php/62806-TBV-ignition-electronics-troubleshooting

good luck....

cliff

 

[magstang1]

I had a truck with a 350 that had the same issue. Turned out to be the fuel pressure regulator. After pressure was built up behind the regulator and the engine was turned off, the regulator would leak fuel past it, flooding the engine.

 

[toyterrific]

Put in new Mercruiser fuel filter with rebuilt Mercarb (807312, electric choke, from Guaranteed Carburetors in Largo, FL) two months ago.
I will check fuel vent. Without looking up in manual could someone tell me where it is?
Hope it's something that simple, Cliff's trouble-shooting process is a bit over my head, I'm afraid.
I will be back to boat on July 4.