Morris Minor Owners Club

Front brakes binding after 1hr on new Lockheed wheel cylinders, not the hole in master cylinder cause of problem but the spring cup length under the piston, only cure is stronger shoe springs.

I can't comment on the spring lengths in the cylinders, I put new lockheed slave cylinders on a couple of years back and had no problems. Pretty meaningless as things can change quick in manufacture.

I can't see either of those springs in the cylinders arguing against the return springs, there are two possible holes that you can get the return spring into the shoe, if I remember right its the innermost one that's correct - but I stand to be corrected on that.

Also that piston looks very discoloured and marked, or is it the light ?.

I really can't see it being the cylinder springs, given their relative size and tension compared to the shoe springs.

That's like comparing the springs from a couple of retractable ball pint pens. The might look a bit different, but there's nothing in it really.

Both of those springs are compressed and then give an outward pressure, of a rather low figure (I bet you can compress either of them with negligable pressure between finger and thumb), compared to the tension of the shoe springs, which we all know can be a brute to hook into place.

Sorry but I just see no way those feeble little cylinder springs are the problem.

The biggest miss idea as regards brake adjustment is that the shoes should be adjusted just short of contact with the drum. Not so.
The pistons to be kept free must exercise - that is that thy must have sufficient in /out travel to be kept free. Sufficient movement of the piston can be achieved by allowing sufficient clearance between shoe and drum obtained by slacking off the brake adjuster one or more aditional notches.

There is no way that the small spring inside the cylinder could generate sufficient force to overcome the main brake shoe return springs.

I also can't comment why the cup spring are longer than the 1996 one, had to use the 2018 new shoe springs instead which are shorter. the piston is a 1996 one I had as spare with the cylinder.