locoboy
|
| posted on 21/7/06 at 08:56 AM |
|
|
Mini Woes
Im working on a 1976 mini at work and its 99% ready for MOT except that i can not get the braking system to work properly.
It has got cooper s disks on the front and standard drums on the rear. Its running a single outlet master cylinder that splits front and rear via a T
piece.
I think its the pressure reduction valve on the rear line that is the problem.
When driving along and braking the rear brakes lock up before the fronts.........well i have not got the fronts to lock up at all as yet!
Even when reversing and then braking i cant get the fronts to lock up.........but the rears do.
I cant seem to get hold of a replacement 3 way pressure reduction valve so i am thinking about fitting an inline reducing valve (one line in and one
line out) then replacing the rear valve with a T piece to split the single line left and right.
Any ideas what kind of valve would be best for my needs?
ATB
Locoboy
|
|
|
|
|
iank
|
| posted on 21/7/06 at 09:05 AM |
|
|
Personally my first step would be to replace the death-trap single circuit brake master cylinder with a split one from a later mini.
I think (but am prepared to be proved wrong) that the cooper S always had split brakes, so it looks like you are using the master cylinder from an
early drum braked car.
|
|
|
locoboy
|
| posted on 21/7/06 at 09:46 AM |
|
|
According to MiniMania the cooper S had this master cylinder
Clicky
Which is just the 'bean can' version of the plastic one i have fitted.
So it looks like the cooper s ran a single circuit too.
ATB
Locoboy
|
|
|
Kissy
|
| posted on 21/7/06 at 10:44 AM |
|
|
Can't you just plumb the reduction valve out for the MOT? If all seals are good and the lines bled you should show plenty of efficiency for the
MOT.
|
|
|
JeffHs
|
| posted on 21/7/06 at 03:22 PM |
|
|
I'd be surprised if it was the valve. I ran a 63 traveller for years and it kept failing MoT on rears - not enough braking. Most testers gave up
and passed it but eventually one refused, so I took the valve to bits and packed the spring to increase pressure to the rears. If it's fitted
correctly, I can't see how it has any influence on the fronts.
Very silly suggestion - are the calipers fitted correctly with the bleed nipples at the top? It is possible to fit them left to right with the bleeds
at the bottom, so you can't get the air out (guess how I know that!)
Jeff
|
|
|
DIY Si
|
| posted on 21/7/06 at 04:13 PM |
|
|
This is the same brake set up on my mini, and I run the later split master cylinder. Mush easier, and I don't think I have a pressure valve at
all. Brakes nice and very quickly. May I also suggest green stuff pads for the front? I found them to give a huge increase in braking performance.
|
|
|
rusty nuts
|
| posted on 21/7/06 at 04:40 PM |
|
|
Have you checked that the brake calipers haven't got siezed pistons ? Also think it would be a good idea to replace master cylinder with a dual
curcuit item
|
|
|
.jpg)
