Fuel Pump Relays

[hack4alivin]

Here we go again….:smt021 Several weeks ago while heading out with our 06 320 the starboard engine quit running and would not start up. Come to find out the relay which supplies the fuel pump and solenoid burned up at the relay pin and burned the relay socket itself. After a week in the service department the parts were received and replaced. New relay and entire wiring harness complete with relay sockets.

Last night when attempting to go out the port engine would not start. Opened the hatch and found the very same relay was well on its way to burning up the relay and socket as well. Knowing something about electronics it appears the pins on this relay are not large enough to support the current being pulled. There are 16 gauge wires supplying the socket so I assume the current draw is no more the 10 amps. When working correctly when I push the start button for each engine to the on position, I can here the fuel supply solenoid click, and the fuel pump running.

Is there something wrong with this design, and has anyone else experienced this problem. This is a new boat for us, and we have not even put 20 hours on it. It had 150 hours when we bought it.

This is one expensive “dock ornament”.

 

[skibum]

Can you check the resistance of the 2 fuel pumps with a meter? I'd pull the relays (I assume that each engine has a pump, and that each pump has its own relay?) and measure it there. That way, you can see if there is a difference between the 2 pump circuits.

If the relay and socket are both cooking, then something is making that circuit pull way too many amps. Most often, this is the result of a short somewhere. Since the wiring has already been replaced, I suspect the pumps themselves. I know nothing about your particular fuel pump motors, but if they have a "normal" coiled armature, it is possible that one of the coils has a short in it. The pump will still run, but the shorter coils will have less resistance and pull more current.

Good luck,
Michael

 

[hack4alivin]

The boat is still under warranty, so MarineMax will be fixing this. My biggest concern is after putting in a new wiring harness that this problem goes away for good. Thing is, the new wiring harness has the same design, which I hope is not the problem.

I agree the contact must be pulling too many amps, but I don’t believe it is the pump at fault since the problem has now happened on both engines, which are completely separate.

Thanks for your thoughts…

Bill

 

[fwebster]

If it helps any, this is the only time we've heard this complaint..........

There is another more likely cause for your problem than wire sizes. Sea Ray uses a type of plug and socket that is made so the pins can slide in the holes they mount in. Sometimes, the pins get pushed back up in the plastic part of the socket when they are assembled and that means you have only a partial pin inside its mating part making contact. That increases resistance and heat and can cause the connectioin to burn and fail as yours have.

This is a known problem to guys who have been around and fixing broken Sea Rays a while. Perhaps the technician assigned to your boat is new or in a hurry, is paid by the job instead of time, who knows. If this occured on one engine, it should be an automatic to pull the plug apart on the other side and check it as well.