96 Mercruiser v6 fuel pump relay problem

[woodduck110]

Hello all, Having a problem with my Fuel pump relay. It won't come on and prime the carbs when key is turned. It usually takes 4 or 5 times turning the key for it to activate. The engine is a 96 Mercruiser 4.3L V6 with electric fuel pump. I have checked the connections and it looks fine. Any ideas what could be causing this? thanks for any info.

 

[gm280]

woodduck110, it could be the relay itself. Even if you hear it click in, that doesn't mean the contacts are not burnt and therefore no voltage is going to the fuel pump. And so it takes a few times to help make enough contact for it to have enough voltage for the fuel pump to operate. If you know enough about how it is wired, you could jumper the relay to see if it runs the fuel pump without any problems. If so, it looks like the relay is your problem. Of course that is if the relay is clicking in when you turn the key. If it isn't clicking in, then you could have an ignition switch issue and not applying voltage to the relay to latch in it to start with... Let us know what happens... :thumb:

 

[woodduck110]

I spoke with a Mercruiser rep on the phone and he said that the relay is actually inside the fuel pump, so if that's the case looks like i'll be buying a new pump.

 

[achris]

That engine doesn't have a fuel pump relay. The pump is powered by the key (sort of) directly. You also will not hear anything when you turn the key to ON. The pump will only receive power under 2 conditions. 1, while the engine is being cranked, and 2, once oil pressure is up enough to close the pressure switch.

Chris.....