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Tips
Tips

hints on rebuilding brake servo?

jd72tr6

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HI EVERYONE, BEEN LOSING MY BRAKE FLUID EVERY WINTER. ALL SUMMER WORKS FINE, FLUID LEAK RIGHT UNDER SERVO AT THE WINTER, ANY HINTS OR TIPS? THANK YOU JIM
 
Jim,

This is one job that I feel is best left to a professional and the prices are not bad out there to get these done. But by it's design, the servo doesn't have any fluid in it, so the diaphragm in it is now probably ruined from the leak that is coming from your master cylinder, which will need to be replaced or rebuilt as well.

PS - you can turn the caps off
 
If your master cylinder has not been to "Apple White" or the other rebuilder it probable needs it. With a little luck you will not need to bother the servo.
 
<div class="ubbcode-block"><div class="ubbcode-header">Quote:]With a little luck you will not need to bother the servo.[/QUOTE]

Unless the fluid contacted the diaphragm.......
 
If it's full enough to be dripping out over the winter; and going on for several years now, I'd say it's a safe bet the servo will need attention soon if not now. Conventional brake fluid will both take the paint off, and promote corrosion of the metal underneath.

But get the MC fixed first, and maybe you'll get lucky with the servo.
 
I'm confused, why is the master cyl. fine all summer,no leaks at all- then come winter, all the fluid drains out?jim
 
I had the same problem with the MC on my GT6, it would be fine all summer but in the winter when the temperature dropped all the fluid would leak out. Then when the temps warmed up in the spring it would be OK. I rebuilt it a couple of times but it was always the same story come next winter.

I finally solved the problem by going to junkyard in the winter and checking the MCs on several Spits & GT6's (this was back when you could still find Spits in junkyards) until I found one that still held fluid. I figured if it's been sitting out herein the field and still holds fluid it's probably OK. I grabbed it for something like $5 bucks and never had a problem again.

Near as I could figure was that in the cold temps the seals would shrink and the cylinder was worn enough that just that little bit of shrinkage in the seals was enough to let fluid out.
 
I put DOT 5 silicone fluid in my MC and clutch system 20 years ago. Car went up on jackstands soon after. Now just getting round to putting car back on road and pedal was still firm. I did all new components when changed to silicone fluid. When I had standard fluid always had issues with paint due to location on firewall.

JIm
 
I went with silicone in both the brakes and clutch a few years ago when the chassis was rebuilt.
 
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