Brakes releasing slowly

[mattie4859]

Since my restoration, the brakes don't release as quickly as they should. The suggested problem is that the vacuum release valve in one of the boosters is not releasing vacuum quick enough when the brake pedal is released. Problem is, I am told they are a specialised unit NLA (plus we can't tell which booster it may be). Anybody any experience with a fix for this, or any suggestions?

Matt

 

[timt]

Matt, I assume you have an RHD car? If so, you probably have two immediate choices (someone may shout me down!):

Find an NZ specialist who can service the servos - not a trivial task. Or, get "new" ones as they are still available, at a price! Linwar (linwar.com) sell them plus master cylinders - UK based so time and shipping cost to add. There may be other sources but they don't stand out at the moment!

I'm aware that one or two conversions to single servo have been done and variants using later model servos ... others with direct experience may advise.

Regards

 

[SteveM]

Mattie,
I had a similar problem on my rhd CSi a couple of years ago. Spent a small fortune getting pretty much everything rebuilt trying to trace the issue. Turns out that the two small brake hoses on the rear of the car - from memory about 6 inches long - were the culprits. The hoses looked in great condition but had collapsed internally. This restricted the flow of fluid - in my case back into the system. I could apply the brakes but they wouldn't release completely - until the pressure drained and then the brakes would come off.
The tricky bit about finding the solution was that the effect was gradual and appeared to be related to heat-sink. I'd get say, the boosters rebuilt and the mechanic would test the car and not find a problem. I'd get the car after work, drive for 20 kms in slow rush hour traffic and the brakes would slowly bind up.
Replaced the hoses and the problem disappeared. Best $20 I've ever spent.

 

[bill]

By all means, REPLACE the flexible brake lines first. Had this problem on my 74...and went through replacing all the calipers before I found out all some of the lines were constricted.

 

[kasbatts]

Hi Matt, I'm in Auckland to and have now owned my coupe for about 5 years
Have rebuilt just about everything on it so may be able to help you out with any problems, For any of the mechanical stuff I have a very good Mechanic friend here in Auckland who works from home and charges very reasonably
He trained and worked on this era of cars so knows his stuff.
Anyway give me a call if you like, would be great to get together for a yarn, and when mines all back together maybe a drive?

Steve

Work number 828 9984
Home number 817 6890