Atomic 4 runs great and then sudenly dies.

[tcatoe]

Atomic four on My P30 is running great now. However after running for about 30 to 45 minutes the engine suddenly dies. It will restart and then die again. I can get it to start with the choke then it dies. Then if I wait for 10 minutes or so it will start right back up and continue to run for another 30 to 45 min.

I have all new filters and new gas line in this rebuilt engine. When the engine dies I notice that the fuel pump is very hot. when I say hot I mean you can not touch it. It is a bulkhead mounted Airtex OEM fuel pump E2014M-3 $43.00, that you get from auto store. It came with the boat new in the box. All I can think is that the fuel pump is getting so hot that it vapor locks and corrects itself after cooling. I have it wired through the OPSS and pulling hot off the coil. I also have the bulkhead brackets grounded to the engine.



Any thoughts on this sure would much appreciated. I have tested the pump and it pumps fine when it is not hot. I cant touch it long enough to feel if it is pumping when it is hot. Do the electric fuel pumps normally run this hot?

[ndutton]

An electric pump needs fuel flow to cool it and I suspect that is the origin of your problem. The tank vent comes immediately to mind. If it's not clear the pump will suck up to a point where negative pressure overwhelms its ability to pump.

As a diagnostic, try running with the fuel fill cap open, see if there's a difference.

[roadnsky]

Do the electric fuel pumps normally run this hot?

Only in hell.
Been there... done that.