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MG MGB Technical - Re-Wiring

Has any tried rewiring a 77 MGB? I am a novice but it seems most of my troubles come from the electrics.
DK Kiernan

DK-
Messing around trying to extend the life of an ancient wiring system by fixing things as they go bad is an exercise in frustration. If you're a masochist, you can make your own wiring loom, complete with soldered connections. I did this when I built my 1972 mgb roadster. After having gone through that agony and expense, I chose to purchase the looms for my MGC, MGA, midget, and TF from the best quality maker. Click on this: http://www.britishwiring.com/ You can't go wrong with these people.
Steve S.

Can a novice do it?
DK Kiernan

http://www.advanceautowire.com is another good source for a wiring harness.
Both British Wiring and Advance Auto Wire will customize a wiring harness for you if you want to make upgrades such as adding headlight relays, modern high output alternators, etc.
If you are going to rewire the car, look at the '78-'80 wiring diagram and see if you want to add an ignition relay. There should be no extra charge for this upgrade and the relay sells for less than $5- at most auto parts stores.
Wiring diagrams are available at http://www.advanceautowire.com click on stock schematics.
Peter Mittler has shared his experience installing a wiring harness in fairly good detail with photos. Do a search at http://www.mgexperience.net ,MGB board, his username is pmittler. He wrote about it in 15 topics detailing the different steps he took.
Kimberly

DK-
The beautiful thing abiut the MGB is that it was designed back in the days when things were assembled by hand, not in modules by robots. In short, yes, you can do it yourself with a little time and patience. Just use the above link to Peter Mittler's work on the subject.
Steve S.

DK I just finished my Ol'Lady's 79MGB and it really was not that hard. I completely gutted all the wiring and rewired it with a harness form Advanced auto wire. I sent them a number of emails asking questions as I did it and Dan there always answered me back right away.

A few things you may want to think about while rewiring are.

Both crimp and solder EVERY connection. This will take you a little longer but you will end up with a far better harness when you are done. If you do not know how to solder just look it up on the INTERNET and practice first. It really is not that hard.

While you have the dash out rewiring in you might as well check out the wiper assembly, windshield washer, heater vents and so on. Again not that hard when you have the dash out.

While you are at it you may as well upgrade the alternator. I used a GM and it works great. Some people will tell you that you have to modify the GM alternator by roatating the cover to mount it but I just made some custom mounts and now I can use a standard GM alternator right out of the box.

I also upgraded all the light bulbs. This does not see like much bot they are a lot brighter. This could be do to the new wiring and alternator but the higher wattage bulbs have to help also.

One thing I did that most people will say I am crazy for doing is I used dedicated grounds. Meaning I ran a large ground wire from the battery to the frame & engine and then branched it out form there with separate ground wire to all 4 corners of the car, out to the front and back and to every major component. I know this sounds like over kill but I used to work on missile systems for the Military and we where always taught not to rely on a chaise ground.

RSF Bob Fowler

"we where always taught not to rely on a chaise ground"

Is that because they are too longue?
Paul Hunt 2

Nice one , Paul.
M Barnfather

Hi DK,

I fitted one of Dan Masters' Advance Autowire kits into my 1978 MGBGT with Rover V8 conversion. It wasn't completely straightforward but, I think, a great improvement on Jo Lucas' original. If you care to contact me off line I'll go through it, flashes, fuse-blowings and all!

Regards

Peter
P L Hills

I have to save my pennies before take this jump. I'm just a poor Air Force guy and it takes a while to save up a spare 400 bones. PLM, thanks for the offer, I'll take you up on that when I have the money (are you anywhere near Fairford or Swindon?)
DK Kiernan

"I'm just a poor Air Force guy and it takes a while to save up a spare 400 bones."

We're having a sale now - $50 off!

http://www.advanceautowire.com

(I used to be an Air Force guy - 1958-1962. I can relate!)
Dan Masters

DK and Dan,

I, too, an ex Air Force - Royal Air Force in my case - and am living about 30 miles from both Fairford and Swindon!

Regards

Peter
P L Hills

PLH, I envy you. That's the most beautiful part of the country (aside from maybe Devon). Going for a summer drive in a sweet car must be pure heaven. Unfortunately, the only car I got to drive around there was a "D" reg Ford Granada, not very fun on the Magic Round-about.
DK Kiernan

DK,

Come over and I'll arrange for you to drive my '78 GT with Rover V8 engine. (And my Tri*mph Stag, too if you like.)!

Peter
P L Hills

Roger that! Next time I'm over, I'll drop you a line.
DK Kiernan

This thread was discussed between 05/05/2007 and 22/05/2007

MG MGB Technical index

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