DISC BRAKES & RESIDUAL PRESSURE VALVE

[ronwilson]

Thanks Ray and Wille for your comments.

The excessive wear on the rear pads points to continued contact bx pad & disc after pedal release and/or more /longer pressure on rear pads than front ones.

We now have the wheels on the ground and a short test drive indicates overheating in the rear brakes/wheels more so on the n/s. Going to start some serious re-examination of the rear disc brakes. This may need a good look at the way kitcars find solutions as Ray has suggested.

[Willie]

Since it is only one side of the rear discs which is binding more then is it down
to your dual cylinder set up which would normally work on one front and one
rear for each brake piston,(defies logic as your diagonal front doesn't wear out as quickly)!!

[ronwilson]

Since it is only one side of the rear discs which is binding more then is it down
to your dual cylinder set up which would normally work on one front and one
rear for each brake piston,(defies logic as your diagonal front doesn't wear out as quickly)!!

Wille, Thanks for your comment. Becoming convinced there's a logic (simple ?) in these affairs but haven't found it yet.The dual cylinder could have been set up one to front, one to rear but wasn't since we already had a servo in system. So, both cylinders feed into one one pipe to the servo and then split front and rear.

Took it for an MOT today-it passed (hallaluia) and recorded 95% braking on their equipment-highest they'd seen. Both rears recorded well and consistent with each other.

Problem (don't tell them) of over braking on rears still persists. We're becoming convinced that the rear n/s cylinder just (hopefully) needs backing off thru adjustment and believe that's possible with Ford Granada ones. Needs closer look. Will post when we try that.

[Willie]

Hope you are right, never knew that there were disc brakes which could be
adjusted for back-off.

[ronwilson]

Hope you are right, never knew that there were disc brakes which could be
adjusted for back-off.

My technical expert (who sourced these Ford Granada/Scorpio rear calipers & customised their handbrake facility to work in the Morris handbrake) assured me that this caliper piston works on a spiral with up to four notches for self-adjustment to keep the brake pads in close proximity to the disc for the handbrake operation. Yesterday, the pistons were compressed and then backed off a notch from their present resting position. Today, after a 20 mile run the problem of overheating was virtually gone. (You could now actually touch the wheel, whereas on Sunday after a 2 mile run you could feel the heat from the hot wheel.)