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 TD TF 1500 - Polarity change

Today I successfully changed the polarity on my 51TD. Following the wonderful instructions posted by many (esp Dave Dubois), I switched the battery terminals, rewired my rear LED lights (because they are polarity sensitive), desoldered/resoldered my optoelectronic fuel pump (also polarity sensitive, and again thanks to the kind instructions of Dave Dubois, who converted it for me a couple of years back), switched ammeter wires, coil wires, flashed the generator and started her up. Everything looks great! As the fuel pump was empty, it took a minute of wild clicking and then slowed down, and the engine started right up!
Thanks again for all the advice over the past few years.

Only thing left to do: make a sign and stick it on the battery warning myself NOT to treat it as a positive ground vehicle any more!
Geoffrey M Baker

Geoff,

There are plenty of CAUTION NEGATIVE EARTH decals out there for later MGs

Jim
JE Carroll

Geoff - Moss Motors carries stickers that say This Vehicle Wired Negative Ground. Cheers - Dave
David DuBois

Here's a classy one for a Jag:

http://www.ebay.com/itm/0244-Jaguar-Etype-Sedan-Negative-Earth-Plate-/221406852597?pt=Vintage_Car_Truck_Parts_Accessories&hash=item338ce075f5&vxp=mtr
JE Carroll

Why not fit a red and a black wire to the battery terminals. It's then obvious which is the earth.


Jan T
J Targosz

Jan - "Why not fit a red and a black wire to the battery terminals. It's then obvious which is the earth."
Unfortunately, the bottom feeders who often work in places that change batteries would not understand the significance of red and black leads - there are those who also don't understand the written word or the spoken word. A member of our local 'T' resister had to get a jump start while out in his TD. There was one of the stickers next to the battery that clearly stated that the car was positive ground and the member also told the guy that the car was positive ground. The nub replied "I know what I am doing" and promptly attached his jumper leads to the battery as negative ground. Fortunately, it didn't hurt the car, but it did do in the battery. My suggestion to anyone getting their MG jumped is to stand behind the guy doing the work with a baseball bat (cricket bat will suffice), ready to tap him/her on the head if they start to attach jumper leads incorrectly. Cheers - (cynical) Dave
David DuBois

I agree, David; it's not even that they are dumb, it's just that they've done this 15,000 times in the past year and they are working on muscle memory, not their brains!
In my case the sign is mostly to remind ME... because now if a garage gives me a jump, they'll most likely do it right quite by accident! I'm the one more likely to automatically attach the cables where I've always done in the past!
Geoffrey M Baker

A short while ago, at a car club tech session, the TC (positive ground) that was going to be worked on had a dead battery. I said, "no problem, I've got my jumpers". The cry went up, "You can't do that, you've got negative ground". Some of the folks still can't figure out what happened to the smoke. Bud
Bud Krueger

This thread was discussed between 15/04/2014 and 17/04/2014

MG TD TF 1500 index

This thread is from the archive. The Live MG TD TF 1500 BBS is active now.