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+--- Thread: Brakes binding when reversing (/showthread.php?tid=5058)
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Brakes binding when reversing - morrisminor - 10-10-2020
When I reverse out of my garage I have to do full lock to miss the house opposite , it almost stops because the brakes bind until I straighten up, apart from demolishing the house opposite is there anything that can be done ?
Then when I drive off forwards it takes a couple of presses of the brakes to centre the shoes, at least that's what it seems like. Once I've driven half a mile they're fine.
RE: Brakes binding when reversing - David Stepney - 10-10-2020
My RP does the same thing. I believe it is something to do with the fact that ends of the brake levers are not quite under the kingpins, which means that the steering geometry tends to pull the backplates forward in relation to the brake cables. Normally this isn't much of a problem, but, in reverse, the trailing brake shoe then becomes the leading shoe and can 'wrap on' as one reverses.
Incidentally, my car has only done this since I relined all the brakes and the bottoms of the levers are now rather further forward than they were. I have also rebalanced the brakes so that the fronts come on before the backs, thus making the car stop somewhat more effectively.
RE: Brakes binding when reversing - morrisminor - 10-10-2020
Thanks David, it's a peculiarity to them isn't it ?
I either nearly stop or there's a squealing noise until I straighten up.
I can see I'm going to have to talk to my neighbour !!
RE: Brakes binding when reversing - AustinWood - 10-10-2020
I find that applying the handbrake on lock (While stationary) forces the compensation to do something. However this is uncouple brakes.
RE: Brakes binding when reversing - Bob Culver - 10-10-2020
The lever balls face the wheels. Whcih way around the cotter is fitted influences operating postion. Some have modified cars so the shoes can slide on the fulcrum; these might behave odd. Unsatisfying though it may be, a long pedal free travel is often necessary.
RE: Brakes binding when reversing - Denis Sweeney - 13-10-2020
I have an early type Ruby July 36 but this has semi girdling brakes at the rear and extended backplate brakes at the front. I have posted previously with regards to my brakes and recently replaced the rear linings and rebalanced everything. All springs, bushes etc are new.
I ran her for the first time a few weeks ago and whilst the brakes may have initially been a little on the tight side to begin with they seemed to have settled and all seemed ok, however on returning from a run of around 20 miles the rears just locked when trying to reverse onto the drive.
I ran her off around the block again and all seemed ok going forward again drove up the drive in first, once there the brakes just locked up again when I tried her in reverse.
I have not had the brakes apart as yet but have checked my photos and the trailing edges of the linings on both shoes extend 1/4” or so beyond the shoe. The from other photos the linings appear symmetrical about the rivets and so this overhang would be there however the linings were fitted.
I intend to remove this overhang as I believe this may be the cause of my problem, but if anyone else has any thoughts I would be glad to hear them
Cheers
Denis S
RE: Brakes binding when reversing - Reckless Rat - 13-10-2020
Denis, have you checked that the pull off springs on the rear shoes are good, and also check that the brake cams are free in the back plates?
RE: Brakes binding when reversing - Denis Sweeney - 13-10-2020
The springs “should” be ok as they were new and the cams were all free prior to boxing it all together again but once I strip it again will check both.
Thanks
RE: Brakes binding when reversing - Bob Culver - 13-10-2020
Hi Denis
The further"forward" the leading edge the greater the self activating effect so chamfering back will help. but unusual for rears to do much at all, esp with the mixed combo. Many Girling shoes have been filed and fitted and seating very poor. The correct pull off springs are strong.
RE: Brakes binding when reversing - Denis Sweeney - 15-10-2020
Stripped the back brakes down on Ruby again this morning, as previously noted the springs were new and they are very stiff and difficult to fit and remove, so think they should be ok. All parts appear in good order, all levers are free and return without any issues and brakes return without sticking.
I backed off the cams to lesson contact between brake and drums cleaned everything down and boxed it all up.
As soon as I tried to reverse out of the garage the brakes locked again!!
Drove around locally and all seems ok going forward but again locks up in reverse.
Stripped it all down again in the afternoon and noticed the drums tighten on the shoes once the three set screws are fitted. So filed all the excess lining material overhanging the brake shoes, bevelled the the linings along the edge that could contact the drum in the inner corner.
Although I had previously filed the front and rear ends of the linings to prevent grabbing I ran the file over the edges again.
Set her up so the cams were as far out as they could be and boxed her up, unfortunately with the same result, great going forward but whilst the brakes didn’t quite lock up this time, they did come on and reversing was not easy.
The new linings I have are from one of our suppliers but are different from the previous linings I had, they do seem to have a higher coefficient of friction then the previous ones.
So I’m back to square one again.
Any suggestions would be much appreciated.
Cheers
Denis S