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MG MGB Technical - Thoughts on Wiring

Hi guys,
Just curious what you guys think, would u rather buy a whole new wiring system for your car from Moss motors, or just have someone re wire the whole thing. Price wise the difference ? I figure why get something new that you know will fail again ? You can upgrade your alternator, ignition, fuse type, and centralize all your fuses. Now getting better amp's from the alternator and "maybe" a guage bigger wires, you could wake up parts that havent neccesairily always been working...Brighter headlights, windsheilid wipers always working due to new connectors, etc, more electrical accesories to bring the car up to date, should be good for V8 conversions and having it be a turn key car, FI injection for the V8 from a land rover etc...I digress... Does someone put out such an upgrade product ? Should I come up with this kit and make millions ? Well maybe thousands... or just buy the moss kit, would love to hear everyones ideas about anything pertaining to this, what you have done, etc ...
James

Might want to try Dan Masters at Advance Autowire

www.advanceautowire.com

greg fast

I will vouch for the quality of the Advance Autowire kit. Every wire seems to be at least two gauges bigger, lots of fuses and nearly everything is actuated through relays. The negative of using his system is that it IS a big project. You have to route, cut, and terminate every wire individually, but you will know the quality of every connection and ground. I'm about 2/3 done with my installation.

Paul

PS - The initial cost of the kit is actually less than the OE style harnesses.
Paul Briggs

James ,
Having just completed a complete electrical harness replacement I can tell you that if you have mechanical ability and apptitude DO IT YOURSELF!!!!!!
My local electrical shop refused to do it at any price,
the local brit-car specialist wanted close to 2000.00,
in doing it yourself you will gain invaluable knowledge of your cars electrical system and save a good deal of cash, there are a number of companies making quality OEM type harnesses out there i.e. Moss Victoria etc. Most are of good quality. As for your assertion that it will just fail again I would say that is incorrect, while there are all kinds of spiffy conversions out there for more amps etc. ( Bosch, Delco ) I would recomend staying as close to original as possible, you can now buy NEW MANUFACTURE lucas type alternators for less than a reman. unit and not have to get creative with the wiring.
As for the Rover conversion......If you want a british car with a big un-econmical V-8, ( gas is'nt going to get cheaper) Buy a shelby cobra, after all the expenditure and alteration to the MGB the cost will be about the same, and yes there are kits and books dedicated to this conversion out there,
I think if you stick to stock parts and repair the car systematically, you will be much happier, and in the end your car will be worth more.
Good luck with the electrics.
Jim
P.S. Pulling a complete harness took me approx 2 days, and as you mentioned I suddenly had accesories back that I forgot the vehicle had, i.e. the annoying seat belt buzzer.
J A Kelly

Replacing the main harness is pretty easy, it is the body harness that is the pain and should be avoided.

"Know will fail again"? What, like in another 30 years?
Paul Hunt 2

I have a new (3 year old) harness and the wiring is fine. I am not impressed with the terminations. The bullet and sleeve approach leaves exposed metal for dirt and oxidation. Also, it is too easy to inadvertently unplug. Has anybody found a clean, water tight termination workaround??
Frank Baker

James,
The wiring harnesses from Moss, Victoria British etc. are very good. All the wires are the proper colour and lengths, and is relatively easy to install.
Terminations on switches and sockets etc. you can cut the old wire off leaving a little piece remaining at each termination. Then when you install the new harness you can use the old wire colour coding as a double check for the correct wires to each device.
As for the bullet connectors To me they are fine. Get some silicone dieelectric grease sometimes called spark plug boot grease and smear some on each bullet connection before you hook them up. You will likly never have another corroded bullet connector problem if you do this. Modern cars have better connectors but in many cases still use the silicone grease. I really don't see the problem with the electrical systems on MGBs. They last 30+ years with maybe a few corroded connectors that can be easily cleaned. I used to drive my '73 B all winter and never had battery charging problems at all. The fuses aren't really a problem as long as all the grommets are in place. I've owned my MGB since new, and have never blown a fuse. As far as the alternator goes, a properly functioning standard Lucas alternator will easily keep the batery charged.
My B has all the original wiring and brushes and bearings changed in the alternator once. I did it myself and it cost about $35 for the parts. Just my .02
cents worth.
Ralph
Ralph

Frank - Check out Posi-Locks at:
http://www.posi-lock.com/
Cheers - Dave
David DuBois

Amen, Mr. Hunt
Jim
J A Kelly

Now I didnt think I was going to offend people with my remarks on lucas wiring design ?!?!?!? THe headlight switch in my 79 B is the same in the Range Rover early 90's models !!! I checked out advanceautowire.com and I think you guys should too, before relpying so you understand more about the question raised in the thread. Its even a saftey concern, if you need a new harness go to advanceautowire.com, no more dim lights etc. Its cheaper too ! Now granted if you already have a new harness from moss etc, im sure your fine with it, everything works, but if you want to upgrade for example a stereo with an amp to provide loud enough amplification with the top down, is what im trying to say, amongst other things, like making it a turn key car, motorized windows, windsheild wipers working all the time etc.
James

Why a new harness??

My experience is that the wiring is fine. The connections are the problem. It is a lot less work to clean up a connection, put some silicon anti corrosion lube on the fitting, make sure it is tight and move on to the next item.

It is done bit by bit, but in replacing the harness you have to do the whole thing AND the connections bit by bit as well.

My '67 harness has some issues. So far all have been solved by working with the connection at one end or the other.

Barry
Barry Parkinson

Barry,
I do agree, I did the same thing in the past. Part of my problem though is the PO messed with some of the wiring, so did the guy who did the paint/bodywork on my B etc, trying to get the wiring hooked up again, smell of rubber insulation burning once. Also im sure people know about the hazard switch in later models causing the turn signals not to operate anymore, I forgot the details but there are threads in the Archives I think (Does anyone know the exact fault of it and the fix for it ? For now I just want to get everything working in the car. Turns signals mainly to get it past inspection. Then get the upgraded system and install it with a better alternator. I do agree that the stock alt is fine for the car and has (knock on wood) never failed me either, along with my starter. But it can still be improved on for modern accesories. Not up totally on my electronics, but would a capacator help improve voltage, and/or a voltage regulator ?
James

The hazard switch affecting the turn signals is simply 30-year-old grease hardening and acting as an insulator instead of a lubricant, in a switch that is rarely used. Dismantle the switch (in a poly bag to catch all the bits!), dig out the old grease, put in some fresh, and reassemble. Flipping the switch back and fore sometimes brings the turn signals back but you are as likely to lose some of the other functions of the switch, or lose the turn signals again after a short time. BT, DT, which was why I opted to dismantle etc. since when it hasn't been a problem.

They are wired via the hazard switch as without that it is possible to have the ignition and fuel pump energised when the ignition is switched off. All cars do this in one way or another.

A capacitor won't improve anything, the one exception being when a good one is used to replace a bad one in the distributor.

Alternators already have a voltage regulator, if yours is faulty then a good replacement will again improve matters. But first measure the voltage at about 2k rpm with minimal electrical load, and then full electrical load, at the brown at the alternator (preferably on the spade *and* the connector, the battery cable lug and each brown spade at the solenoid, browns at the ignition switch and main lighting switch, whites at the ignition switch, fusebox and fuse, greens at fuse, fusebox, brake lights switch etc, blue at the main lighting switch and dip-switch, blue/white and blue/red at the dip switch and headlights. You will probably find progressive small volt-drops along all these circuits, but with bad connections you can get sudden drops which can significantly affect the operation of circuits 'down-stream'.
Paul Hunt 2

This thread was discussed between 14/10/2005 and 15/10/2005

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