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Air in master cylinder 65 Sprite

HAN8L1965

Jedi Warrior
Offline
Some how I am getting back pressure in my master cylinder when I press the brakes or clutch a bubble forms. I bled both the clutch and the brakes no air left in the system. I have no leaks that I can find and I have solid brake pedal and a good clutch. I almost wouldn't care but the over flow is draining down the pedal onto the floor and some day I want to install carpet.

For anyone out there looking for leaks a new piece of cardboard under the car saves a lot of guessing.

Mark
 
I had a leaky master. I had rebuilt it but the seal I used was just a standard cup seal and it wasn't "deep" enough. Anyway, proper seal fixed it up (while, I ended up having to get rid of it altogether anyway but that's a different story).
So, I learned you really need seals designed for this specific application. I also learned you have to really check the bore for pits and wear spots or you will just destroy the next seal and loose your brakes suddenly and that is not good.

Here's my old thread.
 
My Master was completly rebuilt by White Post, I did not have this problem until recently.

Mark
 
Weird. Vented cap? Try pumping the pedal with the cap off and see if you have a geyser.
 
Cap is vented and clean, it isn't a geyser just a bubble which is enough to burp out.

Mark
 
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