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MG MGB Technical - fuel pump installation

I am replacing the fuel pump in my 1976 MGB. I bought a AZX 1307 pump from Moss. My original pump has 3 wires going to it. One is a ground. The 1307 only has one power connection and one groung connection. Where does the third wire go that is on my original pump?

Thanks,
Bob
Bob

According to the diagram in the manual, the fuel pump should only have two wires, white for the power feed, and a black ground. Don't know what the third one could be. What colour is it? Anyone else got any ideas?
Mike
Mike Howlett

Bob - The later MGBs have a radio interference suppressor that is attached between the power connection and ground. The suppressor is usually attached to ground at one of the screws that hold the cover over the pump inside the boot. If you do not get any noise in your radio with this suppressor disconnected, then this connection can be left off. Good luck - Dave
David DuBois

One wire is the ground, the other is power, and the third is mounted on a bolt that screws into the pump. That is the one I am not sure of. Also, there is what looks like an small air intake on the new pump, what do I do with that?

Thanks,
Bob
Bob

There should be 2 small air breather hose barbs on the pump.

One is on the plastic end cap. The other one is on the body of the pump.

Each one is connected to a separate nylon plastic hose, and both hoses are
routed into the trunk and capped off with a "T" fitting.

Inside the fuel pump is a rubber diaphragm. As the pump is working and moving fuel,
it also displaces air throughout the insides of the pump. The breathers makes this a bit
easier as the pump doesn't have to labor against compressed air. The hoses are routed
up in the trunk (boot) to prevent water and road dirt from being sucked into the pump.

Maybe if you look around the area where the fuel pump is located, the hoses for this
could still be there.
Daniel Wong

I would not worry about it Bob. I am assuming the new pump is functioning correctly? I would hook up the air intake though. I have not had any problems with mine in several years and when I was under the car doing some diff work I saw how dirty the pump had become. I guess whatever oil had leaked from where ever had made it's way back there and coated the whole assembly with a half inch of grime.
J Arthurs

This thread was discussed between 06/07/2002 and 07/07/2002

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