Master Cylinder and Booster

Seon

Well Known Member
Supporting Member 3
After market CPP Master Cylinder with Booster mounted on my '58 Impala. Inserted the M/C bleed kit then pumped and pumped til my legs gave out. Called Classic Industries tech line who said that the proportioning valve may be stick. Told him brake lines weren't connected so he said I to call CPP which I did and was put on hold for over an hour. In the mean time decided to pull the unit off the Impala and bench test the M/C. Disconnected the booster off and discovered a piston rod that's suppose to be between the M/C and booster was missing. Got a long 5/8" bolt then chucked it in the lathe and machined a piston rod then inserted it between the M/C and booster. Mounted the unit and now all is good, bled the brakes and wife is a happy camper. All this was done while on hold with CPP who then answered the line.
Told the Tech what I found and he said I must have dropped and lost the piston. Instructed me to take pictures of the M/C and booster separatedly and email to him. Then he'll mail me a replacement but I have to cover the postage. WHAT???
Rather than argue that piston was never there, decided just to send the pictures. I no longer need the piston but decided to get it anyway. Now waiting for him to call back so I can give my my CC numbers.
 

1958 delivery

Well Known Member
Supporting Member 2
Get the correct rod, it will have the adjustable lenght to fine tune the clearance between the mc and booster.

It's not a rod, they buy deep hole master and put them on short pin boosters so they supply a "slug" to use as a band aid. Usually the slug they supply is too long and it pushes the master at idle causing bleeding and braking issues.
I use to only supply the correct master with the matching booster no need for slugs
 

blkblk63ss

Well Seasoned Member
Supporting Member 5
It's not a rod, they buy deep hole master and put them on short pin boosters so they supply a "slug" to use as a band aid. Usually the slug they supply is too long and it pushes the master at idle causing bleeding and braking issues.
I use to only supply the correct master with the matching booster no need for slugs
Sounds like he has a rod???:dunno
 
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