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MG MGB Technical - Fuel pump issue

A friend on mine has a 1978 MGB GT with a electric fuel pump. The other day the car stopped and there was no feed to the fuel pump. I have searched through the Haynes manual to try to find if it is protected by a fuse but found nothing.Is ther a usual fault we can look for.
Any ideas welcome
a goldup

If no fuel is getting to the pump there must be a blockage or break in the line to the pump. The pick-up may have moved (don't know how it can happen) and could be above the fuel line.

If the pump has stopped pumping it may have died electrically or the pump internals may be dead. Check for voltage at the pump with the ignition "on" to confirm the wiring is OK.
J Tait

I presume you mean you have no power to the pump as you mention looking for a fuse. The pump is unfused and is fed by a white wire in the rear harness which joins to the main harness in a mass of connectors by the fusebox, white (up to 77) or white/brown (78 on), the latter having a fourth wire in that connector feeding the overdrive via the gearbox harness. Check for voltage there on both sides of the connector. This is about the only place a disconnection can occur, other than a break in the actual wire, as it then goes direct to the spade on the back of the pump which conveniently projects into the boot on rubber bumper cars. Make sure the other side of the meter or test-lamp is connected to a good earth otherwise even if there *is* power reaching the pump you won't see it.
Paul Hunt 2010

There is an earth supply lead to the pump on the coil housing, it should be visible from the battery compartment. This is open to the elements and may be a bad connection due to verdigris.
c cummins

Did you actually check that the wire to the fuel pump had power, with a voltmeter or test light. or has the pump just stopped, and you're assuming that there is no power?
If it has just stopped, try striking the main metal body of the pump violently. You’ll have to squeeze under the car to do this, or take off the rear right hand wheel. The mechanical points do wear out and a jolt is sometimes enough to kick them over and get them started. You don’t get to do it too often though. The points are part of a fine delicate lever with a spring that switch/click on and off as the pump diaphragm moves back and forth. They are under that plastic cap that sticks into the RHC (in the forward direction) of the boot.
The power wires to the pump runs down from the forward RHC of the boot.
Peter Sherman

Until the original poster comes back and says whether he has no 12v at the pump, or simply that the pump stopped working, we are all wasting our time, it could be almost anything.
Paul Hunt 2010

Sorry to make it clear there is no power to the pump the white lead on the pump is dead. It is not my car. I will pass your suggestions on to the owner.
Many Thanks for your help.
a goldup

Found the problem it was a broken wire behind the alternator.
a goldup

This thread was discussed between 14/06/2010 and 16/06/2010

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