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1972 C10 master cylinder leaking

  
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1972 C10 master cylinder leaking

 
Chevydude350 Chevydude350
New User | Posts: 3 | Joined: 05/13
Posted: 05/24/13
10:00 AM

I have installed several  new (stock) master cylinders on my 1972 C-10 with 350. The top leaks and drips down on the steering column. any suggestions on how to get the top to stop leaking. (or suggest a differnt brand of master cylinder) As we know the master cylinder leans forward.

thanks for the help  

waynep712222 waynep712222
User | Posts: 209 | Joined: 03/13
Posted: 05/24/13
07:32 PM

take the gasket out of the cap...

set the cap back on the master and you fill find it rocks back and forth...

with something square or with a flat end... you will want to gently flatten the flange against the top of the master.. so it does not rock and does not have any HIGH spots so it squeezes the seal evenly all the way around....

sorry... the manufacturers are using the thinnest covers available and they are NOT straight..

i usually spend 2 or 3 minutes with a TACK hammer and a scrap of steel to flatten them..

Image 15652

a small peen hammer also works.. or a medium one   with a tool like this...

Image 13469


that reminds me to send out some emails to at least one supplier of those that  i know about..  

waynep712222 waynep712222
User | Posts: 209 | Joined: 03/13
Posted: 05/24/13
07:49 PM

why does the master leak from the top..... when you depress the brake pedal.. the piston and seals move forward past the tiny fill ports drilled into the top of the bore..  this movement displaces some fluid..  that shoots straight up at the rubber seal..   this is why it drips if the cap does not hold the seal down tightly all the way around evenly..  

Chevydude350 Chevydude350
New User | Posts: 3 | Joined: 05/13
Posted: 06/03/13
11:07 AM

thanks for the suggestion that does make sence!!!! I will try it this weekend!!