4.3 dies after 5-10 sec running

[soulhawaii]

2004 4.3l mercruiser, rebuilt last year.

I replaced the gimbal bearing a month ago, and didn't get a chance to use the boat until today, it sat. Today I put it in the water and start it and it died after 10 seconds. Every time I run it, it dies 5-10 seconds later, does not pop or sputter when it dies, just turns off. I checked the fuel tank vent and it's clear, where do I start with next?

Also when I start it, it takes a second longer to start than usual.

 

[Rick Stephens]

You have an electric fuel pump that is powered by an oil pressure switch or by the starter when cranking. Your oil pressure switch is not working. You crank and get power to the pump, soon as it starts, that power goes away and you run until the bowl empties. Check the oil pressure switch next to the distributor.

 

[alldodge]

What is your serial number?

 

[MichaelBC]

Ricks explanation makes absolut sense but on my engine the oil pressure switch next to the distrubutor is connected to the gauge. The switch for the pump is near the oil filter on port side.

 

[QBhoy]

Hi. My thoughts are around asking if it’s an mpi 4.3 and around when the last time the diz cap was changed out. Also around the mention of it being rebuilt too. Has she ran as she should since the rebuild ?