Older Volvo Penta 5.0 stalls after 1.75-2 hours

[gtimar]

I've got a older Seapro with the Volvo Penta 5.0.

The engine runs great at all rpm up until the 13/4 - 2 hour period when it just dies.

It always starts, I need to push the throttle, but it always stalls again. The longer I let it sit, the longer it runs, so I will let it sit a half hour and get about a half hour to 45 minutes before it dies. If I start it up after 5-10 minutes it only runs 10-15 minutes

All ideas appreciated

 

[captmello]

without more details, the only thing I can think of is a clogged fuel tank vent tube. next time it happens, remove the fuel cap. does it hiss as air rushes into the tank?

 

[gtimar]

I'll give it a try, thanks!

 

[skydiveD30571]

Was thinking the same thing. With a partially plugged vent tube, air can't replace the picked up fuel fast enough which creates a vacuum in the tank and stalls the engine. As it sits for long periods of time, air has time to slowly seep through the partially plugged tube and equalize the tank.