Fuel pump not starting

[tony1b2000]

Hi,

I have twin mercs 4.3 mpi engines. Having starting problems with the starboard engine. Lately, it is not starting as it should. First click on the engine switch and I should hear the fuel pump for a few seconds. ok, so I swapped the relays from the port to starboard engine. The problem I though was resolved as BOTH engines started. A couple days later, same problem with the starboard engine (no fuel pump noise). Next I disconnected and reconnected the harnesses to the ecm. Wow, pump on and engine started!
Today the problem is back! I disconnect and reconnect the fuel pump connector. Now it working again!
What the heck is going on????? I certainly do not want to be 5 miles from shore when this happens.

Suggestions???

 

[Don S]

Re: Fuel pump not starting

Any corrosion showing on any of the connections? Relay, connectors, etc.

 

[tony1b2000]

Re: Fuel pump not starting

Any corrosion showing on any of the connections? Relay, connectors, etc.

Hi Don,

No corrosion at all on any connections. The only item I have not checked the connections for is the oil pressure switch (not sender) which I cannot find.
This is such an intermittent problem!

 

[tony1b2000]

Re: Fuel pump not starting

Has anyone replaced the oil pressure switch? Did you have the same starting problems?