Volvo penta fuel pump and relay issue

[cargarci]

My Engine is 5.0 litters GL Volvo Penta Ser# 4110161641 or 3869BSA or 3868892 (Im not sure what number is the serial).

My boat acted like it was out of gas and had to be towed in. I have done some troubleshooting posted by Don S. This is what I have done so far;
1. With the ignition switch off, verified battery voltage between terminal 30 and 86 at the fuel pump relay socket.
2. put a jumper between terminal 30 and 87.

The fuel pump came on and I noticed that was cutting off as I moved the wires around the area. The 20 amp breaker was bad inside so I replaced with a new one (wires were tight but the rods had broken inside making intermittent contact). As happy as I could be installed the relay back and tried to start the engine. I still had the same problem. I took the relay out again and put the jumper. The engine started with no problems and stayed on.
3. With the engine running and the jumper on the socket I verified battery voltage at terminal 85 and 86. (This should have verified power from the alternator). While the engine still running I removed the jumper and quickly installed the relay back. The engine shutt off after a minute.

4. I replaced the relay with a new one and still no luck.

I dont get it!, I had verified all of the voltages present at the relay socket.

What in the world then?

Thanks in advance for any help!

 

[bruceb58]

Re: Volvo penta fuel pump and relay issue

Put the jumper back in and start the engine. Verify you have voltage at terminal 86 to 85. Thats the terminal that supplies voltage to the coil of the relay. If you have voltage there you may have a bad relay. I would then test the same connection with a test light so that you are putting a load on it. You could measure 12V with no load but have a bad connection enough that it won't drive the relay. Just keep in mind that the ground(terminal 85) here is just as important as the power to the relay


With the relay out you can apply voltage to terminal 86 and 85 and you should hear the relay click. It still may not have good contacts inside but at least you can verify the coil inside is working. If that works, replace the relay.

 

[cargarci]

Re: Volvo penta fuel pump and relay issue

I have voltage between terminal 86 and 85. I have not put it with a light yet. I have replace the relay already susoecting this and no help.

If it is the bracket that connects the relay, how hard is it to replace?

Also I suspect that the orange wire diode might be bad, where is the diode?

 

[cargarci]

Re: Volvo penta fuel pump and relay issue

Ok, I went today and replaced the relay again. As I replaced the relay I noticed that the 86 terminal was pushed down and of course no contact or voltage to the relay.

I am a very happy camper. Thanks for the support.