Brake Servo Rebuild

[63alpine]

I have a nice, original S3 Alpine but have been having problems with the brake servo for a while now. A few months ago I found I was losing brake fluid into the servo housing and a replacement kit fixed the problem, but now the brake pedal sticks on. I believe this is a common problem when trying to rebuild servos and has to do with the piston sticking or binding on the seals. I have driven the car without the servo but want to have the original unit restored so it is working properly. Having tried several times to get the piston to run freely within the servo I have decided to go with a specialist repair to solve the problem once and for all.

Can anyone recommend a specialist who can do the rebuild for me and do it right? I'd like to use someone who is an Alpine enthusiast and someone who has rebuilt original servos before. Any help would be much appreciated as the car is running beautifully and I am looking forward to using it often this season. Please message me or reply to this thread. Thanks in advance.

 

[63alpine]

BTW, the problem recently got worse after a major engine tune-up. Appears the extra performance generated by having a well tuned engine (all 80bhp ) made the servo piston stick more, locking the wheels and causing the brake lights to come on without the brake pedal being applied. When I try to push the pedal the brakes are locked on. Turning the engine off and waiting a few minutes releases the pressure but as soon as I touch the brake pedal again they quickly start to lock.

I hope describing the symptoms helps. Thanks again.

 

[Alpine Bob]

A lot of you may not like this, but my servo has been removed and I haven't had any problems with it at all.

 

[63alpine]

I have tried this route, but mainly because everything else works I want to get this to work properly also (now I probably jinxed myself to a summer in the shop ).

See pic here: http://www.daeth.com/servo.html

 

[65beam]

brake servo

i agree with bob,take the servo off and go with the .700 master for series 2 cars.you'll never worry about brake problems again! i have many cars with this setup . if you want to keep the booster for looks;removethe booster,take all the guts out of both cylinders.go to somebody that can weld aluminum and have them weldtwo plugs in the openings.take it home and put the empty vacuum chamber back on.bolt it to the car.connect the brake lines in the proper locations,bleed the brakes and drive it .i have several cars this way and have trouble free brakes and have had for many years. it works!

 

[am99ey]

Won't you loose a lot of break power this way? I just had my servo rebuilt.
(not in use yet..)

 

[Green67Alpine]

If the servo is removed do you have to install a larger master cylinder ?

Tom J

 

[V_Mad]

Sticking is a common problem.

Firstly, the rubber vacuum seal backing that they supply with most repair kits is too stiff/thick. I reused the old spongy backing.

Secondly, you need to use some special grease. I found that silicone grease works well.

Thirdly, when cleaning the vacuum cylinder, get a fine cross honed finish, not a polished one.

 

[britbeam]

If the servo is removed do you have to install a larger master cylinder ?

Tom J

If you remove the servo you should use the smaller ID master with the proper size wheel cylinders. I think what we need are balanced systems where all components work together size wise.
Dwain V6 Krazy

 

[65beam]

brake master

the cars without boosters used .700 size masters,the later cars used .875 masters.i use .700 on all my cars and no servo units.i have done this for twenty something years.i have driven them all over the U.S.,pulled my popup camping trailer and luggage trailers with no problems.my series 4 has the original size wheel cylinders,my series 5 cars have the original size wheel cylinders and my harringtons also have the .700 master with no servos.the only cars i have with servo's are my 69's.they are different in that the servo is hooked up to the front brakes only.that's another story.i guess the moral to my story is:mount a .700 master ,do away with the servo and enjoy for many years.

 

[Jeff Scoville]

Or since you want it to be original and work (as you said twice), contact this guy.

http://cgi.ebay.com/ebaymotors/Brak...8QQihZ018QQcategoryZ10076QQrdZ1QQcmdZViewItem

 

[Pumpkin]

whoa pine

OK You>>>>
pulled my popup camping trailer and luggage trailers with no problems.

Is it more or less advantage to use the larger MS or smaller one? I have a older pop-up and was planning to pull it around?? Series ll with an OD tranny and a 1725 engine.. I have both the .700 freshly over hauled and a new kit coming for my larger one.

BTW, doe's any one have a curled pipe for the separate master /resivoire, mine seems to be sweating out?

Thanks
chuck

 

[65beam]

brakes

i use the.700 master and have for years.keep in mind also that i use gears to slow down also .plus if you want extra braking for a trailer install an electric trailer brake setup.Tiger Tom has used his tiger to tow a car trailer for the many years that i have known him.electric trailer brakes.no problem chuck.i have driven L.B.C's with worse brakes than we have.

 

[Pumpkin]

whoa

i use the.700 master and have for years.keep in mind also that i use gears to slow down also .plus if you want extra braking for a trailer install an electric trailer brake setup.Tiger Tom has used his tiger to tow a car trailer for the many years that i have known him.electric trailer brakes.no problem chuck.i have driven L.B.C's with worse brakes than we have.

OK now that we have spent some time on that one, GOOD info too.

Now a friend has a Later Tiger, with a servo , the unit had been redone, and is still hard pedal. Her car is equiped with hand control and it is too hard for her to operate by hand, then if straight running by foot it is still too hard for normal operation. It is important that we can figure this out, she loves to drive it. HELP
Chuck

 

[P. Scofield]

When I try to push the pedal the brakes are locked on. Turning the engine off and waiting a few minutes releases the pressure but as soon as I touch the brake pedal again they quickly start to lock.

It's called a Servo-Rebuild. Go for it. Have the Aluminum cylinder brass sleeved and you will never touch it again.

P

 

[Jeff Scoville]

It's called a Servo-Rebuild. Go for it. Have the Aluminum cylinder brass sleeved and you will never touch it again.
P

Paul, I think that is what he wants to do, he's just getting info he didn't want.
Didn't you use Apple hydraulics or some such?
Not trying to bitch here, but let's try to answer the question being asked. It's like telling the guy with the 4cyl that isn't running right to fix it with a V6.
Truth be known, last summer I installed this

http://store.summitracing.com/partd...WIL-260-3372&N=400196+304660+115&autoview=sku

on my S IV with no booster (all else remaining stock) and it is the BEST braking Alpine i've ever driven. Fixing the servo is the question at hand. Any recomended sources for a rebuilder would I'm sure be appreciated.

 

[Series3Scott]

Scofield and others have had theirs done by White Post Restorations in Virginia.

http://www.whitepost.com/

Expensive, but well done.

I have yet to rebuild mine - it's simply bypassed, and brakes fine.

 

[65beam]

brake servo

my point was simply this: after many failures and many rebuilds by some of the best in the sunbeam world,you eliminate the problem and fire the booster.it's gone and will never bug you again.

 

[P. Scofield]

my point was simply this: after many failures and many rebuilds by some of the best in the sunbeam world,you eliminate the problem and fire the booster.it's gone and will never bug you again.

That's because they don't do it right. A basic rebuild with with a steel wool buff job and some new rubber parts is only a temporary fix. Aluminum, rubber, and moisture don't mix! Eliminate one...............

 

[PaulK]

What ever happened to Paul Norton, he had some great info on servo overhauls?

Paul