Removing the gearbox earth cable

[neilbardsley]

I was under the car and was going to remove and clean the contacts on the earth cable but then I noticed that the bolt holding it to the gearbox was also a bolt securing the gearbox so become worried it might move, and I would not get is back in, as I had the car jacked up on one side only?

Next I wondered if the bolt securing the cable to the body had a nut on the other side or if the body was threaded?



Sent from my Redmi 7 using Tapatalk

[Gary71]

The body one is a stud welded into the healboard. The gearbox one should be fine if you just take the one out.

[Winston Teague]

Hi Neil, as a rule of thumb, you shouldn't choose a bold that has any movement in it for the earth point. The ideal is a stut or nut welded to the body for one end and a nut on the engine or gearbox that is on a stud, or a bolt that is done up tight, with a bit of coppers lip or similar on an aluminium casting. Absolutely not an exhaust manifold stud (squashy gaskets and heat based corrosion) and not engine mounts (rubbery). The bolts should not clamp more than 2 surfaces together (Lotus used the very substantial bolts in the engine bay that go through to the front suspension mounts on the chassis as the earth on Elans, this was fine when new, but it also sandwiched a layer of fiberglass, and after a few thousand miles of vigorous driving the fiber glass thinned with chafage, and whilst the lights worked well at rest, of at home, they would flicker or go out completely in corners! W

[neilbardsley]

Thank you. I will only clean one side of earth strap then. I did try to undo the weld bolt but didn't try very hard and thank goodness!!

Sent from my Redmi 7 using Tapatalk

[Peter Roberts]

I suffered for years with my starter motor churning over very slowly as if the battery was dead until it eventually fired into life. During my recent restoration i considered converting to 12v but the consensus on the forum was that if the cabling was correct, particularly the earth, then there should be no problem with the 6v system. And they were right.
I got the starter and dynamo properly reconditioned and then set about the earthing. On the front from the battery i drilled an extra hole in the body about 1" from the existing earthing point. I then made up a copper strip from some piping, drilled two holes in it and double bolted the earth strap to the chassis. At the rear i cleaned up the existing standard earthstrap to the body and installed a second one which went directly from one of the started motor bolts to the U tube that supports the gearbox bell housing.
As a result the engine flies over on starting as if it was 12v and the cost was about a fiver for an additional earth cable.

[Mike Smith]

The bolts that secure the Earth Cable to the Car were Brass and 14 across the flats

You will find them at PRS