MG-Cars.net

Welcome to our resource for MG Car Information.

Recommendations

Parts

MG parts spares and accessories are available for MG T Series (TA, MG TB, MG TC, MG TD, MG TF), Magnette, MGA, Twin cam, MGB, MGBGT, MGC, MGC GT, MG Midget, Sprite and other MG models from British car spares company LBCarCo.

MG MGB Technical - And Yet Another Electrical

1966-B / + earth. I was replacing the original fuel pump with an AC that I had until I start the restore on this car. I took the cap off the original pump and the diod was melted but the rest of the pump was in good shape. Before hooking up the AC pump, I tested the leads and got a continuaty reading when I tested both wires together with the ohm meter and also received a full reading when I tested each wire to the earth of the vehicle. It seems that I should get no reading when testing the black wire to the earth of the vehicle.
SORTA CONFUSED AND THANKS FOR ANY HELP.
Steve C.
Steve C.

Steve - The black wire to ground should read continuity regardless of the polarity of the car. The white wire is the power wire and in your case should read -12 volts when the ignition is turned on. Reading continuity to ground on the white wire is probably normal in that you will read to ground through the coil which is only about 3 ohms (a bit hard to read on a standard multimeter. The melted diode in the SU pump is probably the result of it's self destructing as there is nothing external that would cause it to go unless the voltage had been reversed. I can restore the original SU pump and convert it to solid state if you are interested in doing so. Contact me at the above e-mail address if you would like more information.
Good luck - Dave
David DuBois

This thread was discussed on 17/02/2003

MG MGB Technical index

This thread is from the archive. The Live MG MGB Technical BBS is active now.