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 - Central Ground to Front Wiring?

I've seen some discussion about lights and the need to have good grounds. Sounded like there was a central ground for the front wiring harness going to all the front lights etc.
I am going to replace all bullet connectors and want to make sure I have clean ground to all the lights.
Is this located in the front somewhere on frame, coming off engine block or where would I find or locate for best results.
Thanks,
Doug
DT Toms

Doug - The ground distribution point is about the mid point under the slam panel. This is a point where a little bit of corrosion can cause a lot of problems, including overheated wires at the connection point. Cheers - Dave
David DuBois

David,
What is the slam panel? Is that the last piece of sheet metal below the bumper?
I assume there is a bolt terminating the central ground there. Should I just take that off, wire brush to clean metal, clean the terminals, reconnect and then protect with laquer? Or should I establish a new termination point better protected from corrosion?
Best regards,
Doug
DT Toms

Doug; My 74 has a grounding point on the passenger side of the inner fender panel just in front of the fuse box. There are no other ground points toward the front. There is also a ground point behind the fire wall in the passenger foot well area, it's located under the wiper motor meaning the wiper motor needs pulling to service it. The other ground point is in the rear under the license plate bracket mounting screw.

Several years ago I had a 68 GT and as I recall there was a ground point under the car but I don't recall where it was located. Dave has an early MGB and I'm sure his information is correct for his car and other cars. I assume there must been a change based on my car, it has the original wiring. I had 71 parts car about 5 years ago but I don't recall where the grounding was other than the one above the passenger foot well. It didn't seem important to remember at the time, I was wrong.

I believe the panel under the hood in front of the radiator with the hood catch is referred to as the slam panel

Clifton
Clifton Gordon

Later cars behind the fuse box, below the start relay.
FRM
FR Millmore

Doug,

Check Paul Hunt website and you find advice about additonal ground point. Its worth to have a look
Regards
Peter
Peter van de Velde

Doug - The proper name for the slam panel is the bonnet latch platform. It is the horizontal panel where the bonnet latch is attached. I am not sure where the actual ground point is, but it come up and is distributed to the lights through a 4 way bullet connector under the the bonnet latch platform just to one side or the other of the bonnet latch. It is a nearly inaccessable spot to work on without removing the grill. Cheers - Dave
David DuBois

Thanks all. I currently have the grill out to look at these connections so I should be able to find the grounding point there in the front. Also sounds like there is multiple places I need to check ground conditions. Thanks much.
DT Toms

There is no grounding point under the grill on my 74 and there was none there on the 71 parts car I had. The double bullet connectors can be a problem if they haven't been changed. Sometimes they will break apart or split, it's a good idea to inspect them and replace any that are bad. Use dielectric grease for assembly.

Clifton
Clifton Gordon

Folks,

If you are concerned with originality, search long and hard for the original earth/ground points. Then clean them back o bare bright metal and make good connections from the cable. A good connection is one with a ring connector soldered or crimped on. It is NOT a wire wrapped around a self-tapping screw! I'd use a star-washer as well to improve the connection.

If, however, you are more concerned with functionality than originality, provide a separate, good earth/ground connection for each circuit; the car's bodywork will still proved the earth return path but corrosion around the individual earth/ground point would then take out only one circuit. I see no reason to perpetuate what I believe to be a manufacturing convenience and a poor engineering practise.

Regards

Peter
P L Hills

Doug - You will not find an actual connection to ground under the Bonnet latch platform (notice the proper terminolagy). what you will find is the wire that goes to the actual ground point going into a 4 way bullet connector, with wires coming out of the connector and going to each each headlights. Peter in the UK has the right ideas about how to get a good ground. Cheers - Dave
David DuBois

This thread was discussed between 15/04/2007 and 20/04/2007

MG MGB Technical index

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