Welcome to our resource for MG Car Information.



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 - Charging problem solved

More than a week ago I started a thread about a fluctuating volt meter and generator light remaining lit. As it turned out I had a charging problem that drove me crazy. Car is just finishing restoration and being started for the first time. Generator was supposedly rebuilt, the regulator was NOS, and a new wiring harness from the reputable RI wiring. The generator appeared to function and even after swapping out the voltage regulator for a used one I had lying around the light would not extinguish. Research through the BBS and numerous emails exchanged with Bud Krueger kept pointing to the regulator. I had cleaned the contacts on both of them with emery cloth several times followed by contact cleaner. Still no luck so following one persons example that he filed the points I felt I had nothing to lose. Sure enough that did the trick.

The lesson I guess is the points in the regulator like the fuel pump are a real source for unreliability. I have had Dave covert the Fuel pump, which had not functioned initially having sat around as the restoration stretched over 10 years. But since Bob Jeffers passed away his solution is no longer an option for the regulator.

Therefore, it is hoped that someone in the MG community with the knowledge, skill and time will see the need step up to plate and begin converting regulators to pointless. Otherwise I guess I will carry a file in my car as they were already in the original tool kit. I guess the factory was aware of the problem from the beginning.


R Brown

Bob -

The owner of an auto electric shop near Orlando is in the testing phase of a solid state regulator that he is designing to fit inside the original Lucas case. He is designing for a number of cars and bikes that use Lucas regulators. I believe that he will be completed in time for GOF-South in April. I'll post on the BBS when they are available.

- Lonnie
LM Cook


Check the archive plenty of posts detailing how to build your own solid state regulator. The task is not too difficult for someone with soldering and fabrication skills.

G Evans

Your experience is interesting. I've always been wary of new mechanical regulators. The relay contacts are critical, as they are subject to pretty severe use. Back in the dark ages, when mechanical regulators were the only game in town, manufacturers knew how to make them. I'm not sure that the formula has persisted through to the modern ones. It's easy to make something that looks the same, seems to work well for a while, and then quits when the relay contacts get burned.

As for me, I'm still using the regulator that came with my car. It has a 1953 date code. I cleaned the contacts, readjusted the relays, made sure the relays closed and opened at the right voltage, cleaned the case, and put the sucka back into the car. It's working fine, and probably will for another 50 years.

By the way--at any good electronics store, you can get a special file for cleaning relay contacts. It's a thin strip of metal with diamond in the surface. It won't leave any abrasive embedded in the contacts (which would interfere with getting a good contact), as sand paper might.
S Maas

Have to disagree that the regulator points are not reliable. Most likely the NOS one had corrosion from sitting and not use. Since my TD came into the family in the 70s, I replaced the original 9/51 regulator with a new Lucas one in the 80s, I have not had the cover off of it since then. A key trick to cleaning points after filing or sanding is to use a piece of something like a business card and run that between them several times to remove any grit. Particles of sandpaper or emory cloth remain and keep the metal from touching if you don't do this. George
George Butz

Here's another alternative to the Lucas 2 bobbin regulator. It can easily be hidden inside the original Lucas regulator case.
Lew Palmer

The best file for the regulator is a crisp one dollar bill folded in half. The paper is just abrasive enough without leaving any residue. A couple of quick passes while manually closing the points will do the trick.
D. Sander

Great idea Dave
Can you send me a couple to try?


Rod Jones

I'll make you a deal, I'll send you five for only $20 ;-)
D. Sander

You must be form Massachusetts Dave


Rod Jones

The striker surface from a mtachbook does wonders, especially when broken down on the road, but who carris matches anymore?
We also used the matchbook for rough point settings in a pinch
I picked up a NOS Edsel regulator with clear cover pretty cheap on Ebay. It can handle a lot more current than the Lucas generator can muster and I can adjust voltage and current limiting the old fashioned way- tweaking the spring brackets.

Go to They do a solid state conversion that fits inside the original regulator. The cost is 100. I wish I had found them before buying my very expensive alternator. I am now on my third replacement.

Jan T
J Targosz

I agree with others that the original mechanical control box is NOT a source of unreliability. Would you expect any component to last 65 years and still function with a simple adjustment and cleaning? Certainly not any electronic item, new or old. But the Lucas control boxes do last this long and are infinitely rebuildable.

As a side note, I pulled a factory rebuilt unit from its 1950's Lucas cardboard box, installed it in a car, and it has been in continual service now for ten years. Even after 50 years of storage it needed nothing!
Steve S

This thread was discussed between 19/11/2014 and 21/11/2014

MG TD TF 1500 index

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