• When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.

Replacing Master Cylinder

I don't think a parking brake is a good backup either.
It's not a normal response so you lose 2 or 3 seconds or more trying to locate the pedal.
And if your brakes do fail and then you only have rear brakes from the parking assembly.
Try stopping from 50mph or more with just the parking brake you will quickly get to the lockup point on the rears and the car will hardly slow down.
Then the rear will try and kick out on one side or the other.
It's a bad feeling. Try it and report back.
People call it an emergency brake but I hope I never have that emergency.
I am in 100% agreement
that the OP should make an
attempt to upgrade his
braking system for safety's
sake. It won't detract
from the cars value, and
certainly could save
someone's life.
 
Welcome, OP, to one of the most uncomfortable, inconvenient jobs ever, and with a poor selection of suitable tools, to boot.

I have better luck using "medium" deep sockets. I've found that standard sockets are too shallow and traditional deep sockets are too long and get hung up on the pedal and linkage.
Stanley makes a set of medium length, and that at least used to be available at wal-mart.

Those, along with several different lengths of extensions and "wobblies" and/or U joints and a fine tooth ratchet will usually get the job done.
 
Last edited:
Disconnect the battery while the door is open for hours, pull the front seat out.
Throw a few moving blankets or outdoor furniture cushions on the floor.
It really helps and it's worth the little bit of extra effort.
 
I've also pulled the bolt from the pedal to MC link to allow the pedal to swing back out of the way.

Be aware the nut is self locking and the contact for the wrench/socket is very shallow.
 
Last edited:
Ohhh lord what a dooozey! Going to give it another go this afternoon. I will report back. Thinking a seat removal may be the right call. Thanks everyone!
 
If you don't have a wobbly socket take a u-joint and tape it with electricial tape not real tight then wiggle some.
 
Kobalt (and I'm sure others) have extensions with a wobbly/not wobbly end.

Put socket on to first click- wobbly...push to second click- not wobbly.
 
Mission Accomplished. The extentions, uni adapters, and deep sockets did the job. 13mm. The old MC was in terrible shape and should not have been sold to me as is, very unsafe. I got the car from a shop in Ohio who said they had just done a "full brake job". They did put on new drums but didn't bother to check the MC. (Pictured) Just goes to show...
 
Old Master Cylinder

20240426_163539.jpg


20240426_163534.jpg
 
67 Coronet. Did a total front end rebuild/replacement. Including the dual cylinder MC. Turned out I had been driving on rear brakes only, but it still stopped.
 
I have heard this point/argument made as well. I would be interested to hear the arguments on both sides.

I am keeping this car 100% stock, so for me it is less about better or worse, but about restoration.
Sorry it took me so long to reply.

That makes sense. I would probably go with the dual MC, but I can understand why you go the other way.

You probably do this already, but make sure you check your levels every time you go out. That single-pot does not hold much extra fluid. Before I did the Wilwood swap, one of my front brake lines was leaking at the cylinder (the flare was all wonky). Fortunately, I saw the wet spot on the floor before I left the house. The crazy thing is that my MC was nearly empty when I checked it! I don't know if it was leaking when I last drove it or just in the garage, but things could have gone very badly if I didn't take a look before I left.
 
Sorry it took me so long to reply.

That makes sense. I would probably go with the dual MC, but I can understand why you go the other way.

You probably do this already, but make sure you check your levels every time you go out. That single-pot does not hold much extra fluid. Before I did the Wilwood swap, one of my front brake lines was leaking at the cylinder (the flare was all wonky). Fortunately, I saw the wet spot on the floor before I left the house. The crazy thing is that my MC was nearly empty when I checked it! I don't know if it was leaking when I last drove it or just in the garage, but things could have gone very badly if I didn't take a look before I left.
Thanks for the reply. Yeah a dual pot may have been the way to go in hindsight. I am going to be moving soon and may have to put the car up for sale, so I didn't want to get too in the weeds.
Good tip. I will check frequently, along with all the other checks that I do obsessively!
Have a good one!
 
Auto Transport Service
Back
Top