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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 - TD Brakes

I have not used my TD for over two years now and need to get it MOT'd.
It usually sails through with no problems, but, i have never been impressed with the brakes. I realise it's an old car and does not have a modern braking system.
Is there any way i can test the brakes ? Is there some formula, like, the car should stop within so many yards / metres from a given speed?
Any help would be much appreciated.
Derek
Derek

It might be worth while to pull the drums and clean the shoes with brake cleaner...then re-adjust the little adjustors as per the manual.
gordon lawson - TD 27667

Derek - While doing the job that Gordon suggests, check that all the wheel cylinders are working as they should and not sticking (when we got our Magnette a number of years ago, the brakes were underwhleming and I found that 3 of the 6 wheel cylinders were frozen in place - Cleaning them up and getting them to work gave us acceptable braking). Also check that the front cylinders are pointing in the correct direction togive the necessary servo action that is suposed to occure witht he twin leading shoes at the front (look at the pictures in the shop manual). Cheers - Dave
David DuBois

Many thanks Gordon and David for the advise.
I will follow the advise but i would still like to know if there is a formula for brake testing ...... yards to stop from a given MPH ?

Thanks again guys......... very much appreciated.
Derek
Derek

The brakes are all anyone could ask --exactly 141 feet to a dead stop from 60 MPH-short of using an anchor: I don't see how that could be improved upon for it represents a stopping force equal to about .8G, generally referred to as 80% braking efficiency, and is close to the coefficient of friction of rubber on smooth asphalt. Beyond that point you slide, the coefficient of friction decreases, and your stopping distances increases.
Brake fade is practically non-existent although I did notice a slight trace after the aforementioned stock MG race--20 laps and 80 severe, applications on a hot day.


http://www.mgcars.org.uk/mgtd/mgtd_mg_on_trial.htm
gordon lawson - TD 27667

Derek, I thought the "Orginal MGTD" web site used to have a period Road and Track magazine article on the TD which would have given the best figures that they were able to obtain when the car was new. However I see that it is not on the site, so if someone on the bbs here has a print they could probably give you the braking distance at speed.

LaVerne
LED DOWNEY

Hello Gordon and Led
Many thanks for the info. Thats exactly what i was after. Having said that, Gordon, would you happen to know what the distance would be for 40 and 50 MPH?

Thanks again
Derek
Derek

BRAKING EFFICIENCY:
(checked with standard brake efficiency meter)
60% (at 30 mph stopping distance is 50.2 ft.)


The Lockheed hydraulic brakes, with two-leading shoes at the front and leading and trailing shoes at the rear, are amply adequate to the car's performance. Heavy pedal pressures are not required and, as a test, the brakes will stop the car in a straight line from 50 m.p.h. with the driver's hands off the wheel. There was no sign of fade in the arduous conditions of the test, and after extensive use both while taking the performance figures and during many miles of normal motoring, they did not deteriorate nor did the pedal travel increase to any great extent.
gordon lawson - TD 27667

Thanks for all you help Gordon and others.
I have checked offside front and found one of the cylinders was stuck fast !!!
You may be wondering why i didn't check these things before posting my first plea for help. The reason being i had the brakes overhauled by an "mg specialist" and i have only driven about 200 miles since and the car is always garaged and never driven in the rain. I can't believe the cylinder would have siezed had it been properly copper greased. Also, i found the wheels were put back on the wrong side of the car...... so the holes didn't line-up with the holes in the brake drum for adjusting the brakes!!
I will not be going back to that particular "expert" !
Anyway, many thanks for all the suggestions and information..... it is very much appreciated.
Regards
Derek
Derek

Derek... the wheels are not side specific... just unbolt and turn until the holes line up....
gordon lawson - TD 27667

Hmmmmm .......... that is interesting Gordon. I was just about to beg to differ when i thought.... check in the manual first !!
The manual says to adjust front brakes, remove hub cap and wheel, then adjust through hole provided in the drum.
So, NO holes in the wheel through which to make the adjustment. I can only assume a previous owner decided it would be easier to make the adjustment through the wheel and drilled the holes himself.
It does make sense I guess.

Derek
Derek

All four of my wheels have a hole which will line up with the hole in the drums... as long as they have been lined up before bolting on....
gordon lawson


Derek, My late 51 TD has holes that align on all 4 wheels and drums. Another very early TD in the area has holes in a couple wheels that align, and the no holes, or ones that don't align in the others. Evidently there was some production change along the way, and wheels have been mixed over the years. Years ago we had annual state vehicle inspection. The TD would never pass on the machine, so they would have us drive it about 10MPH, and skid. If it left 4 even skid marks, that was good enough. It frequently would only leave 3, and back to the shop. I still use that method if any doubt about any one wheel working. Although not power, the pedal effort is not that high, and shouldn't feel that much different that a modern car. When the cylinders start sticking, it requires much more force. Lastly, the badly designed wheel cylinders have no moisture seal, and it doesn't matter how they are rebuilt- if you don't drive the car regularly, the piston rusts and they stick. Silicon brake fluid minimizes this. George
George Butz

Many thanks Gordon and George.
I have now found 3 out of 4 front cylinders siezed .... no wonder the brakes didnt seem tooooo good!!
I'm sure by the time i've finished the brakes will be up to the standard you mention George...... i hope so!
All the best
Derek
Derek

Amazing how well they stop when all of them work, but man, take away the fronts or the rears and ........!!
gordon lawson - TD 27667

FYI, if you use the big green MG TD,TF,....manual, the illustration of the front brake cylinder installation on the backing plate is wrong. The cylinders are reversed, up should be down and vice versa. It took me several trials to discover this while I attepted to rebuild the fronts and improve my braking using this manual.

Once you get them oriented correctly it stops great!!!
david

This thread was discussed between 21/04/2006 and 25/04/2006

MG TD TF 1500 index

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