Brake master cylinder ??? (pics)

-
mullinax95

mullinax95

Well-Known Member
Joined
Oct 25, 2006
Messages
11,311
Reaction score
340
Location
Anderson, SC
I have been converting my car over from drum brakes to disk brakes on the front. I have been posting on another thread. Start at post #17.

http://www.forabodiesonly.com/mopar/showthread.php?t=27418

I have got everything ready to go and trying to mount the new disk brake master cylinder and removing the old drum brake master cylinder. I can't get the dang push rod out of the old master cylinder. I tried removing it while it was still hooked to the brake pedal, tried removing it from the master cylinder and finally remove the internals of the master cylinder without any luck. The new master cylinder is definitely a bigger bore size even though they look the same in the picture.

What do I need to do here? Get a adjustable master cylinder rod? Get the mopar later model master cylinder?

Cuda boot area 011.jpg


Cuda boot area 012.jpg


Cuda boot area 013.jpg
 
put it in a vise, attach vise grips on it and use two wrenches like fulcrums. how is the piston held in on the new master???? a snap ring? should be. do you have a new pushrod rubber ratainer? if not take a piece of 1/4 fuel line and slice it the width you need and then put a little v notch in it(front to back) so it has room to compress...
 
redfastback said:
put it in a vise, attach vise grips on it and use two wrenches like fulcrums. how is the piston held in on the new master???? a snap ring? should be. do you have a new pushrod rubber ratainer? if not take a piece of 1/4 fuel line and slice it the width you need and then put a little v notch in it(front to back) so it has room to compress...
Click to expand...

OK I'll try to again.

The new master cylinder just has a holt that the rod goes in without a snap ring or any indication of anything else that goes inside the whole to help hold the rod. It is just smooth around the edges until it gets to the bottom of the hole.

If I have to cut the rod it will not be the proper length will it
?
 
Got it!

Thanks fellas!

I didn't know I had to get rude with it. I put in the vice and hit with a 2lb hammer.

The rubber end stayed on the rod so that is good right? Although the hole in the new master cylinder is bigger that the hole on the old one. Does it really need to catch and hold in the new master cylinder? It seems that it would have too.

Cuda boot area 014.jpg


Cuda boot area 015.jpg
 
your new mc should have a new rubber with it. DONT drive the car without the rubber, it holds the brakerod in the mc. if you were to push the pedal, and the pedal came back and the rod fell out of the mc, no brakes
 
i guess what i was after was what is holding the piston in the mc? old drum ones have a metal piece with 2 screws and the disc ones have a snap ring.
 
redfastback said:
i guess what i was after was what is holding the piston in the mc? old drum ones have a metal piece with 2 screws and the disc ones have a snap ring.
Click to expand...


The old one has a piece of metal shaped like a tear drop with one screw holding the piston. The new one well I'm not sure what's holding it in but there is nothing for the eye to see. I guess you can tell by the pictures.
 
sweatybetty said:
your new mc should have a new rubber with it. DONT drive the car without the rubber, it holds the brakerod in the mc. if you were to push the pedal, and the pedal came back and the rod fell out of the mc, no brakes
Click to expand...

No rubber with the new master cylinder.

Do I have the wrong master cylinder? I got a disc brake master for the year and model of my car. When I stick the rod in the new master cylinder with the old rubber still on the rod it does not stay.

???
 
I think you may have a M/C for power brake applications. There should be a grove inside the M/C to hold the rubber keeper. It is a tight squeeze when pushing the rod into the opening. Check your old M/C against the new one and see if there is a retaining grove in the new one.
Bob
 
gerty said:
I think you may have a M/C for power brake applications. There should be a grove inside the M/C to hold the rubber keeper. It is a tight squeeze when pushing the rod into the opening. Check your old M/C against the new one and see if there is a retaining grove in the new one.
Bob
Click to expand...

Your right Bob.

I did some checking last night and using the part number it is a MC for a Fury most likely with power brakes. I found a MC for my year and model with manual disc brakes and trying to find it this morning.
 
get a 73-76 a body power disc master with a 15/16" bore. it will have a groove for your pushrod.
 
redfastback said:
get a 73-76 a body power disc master with a 15/16" bore. it will have a groove for your pushrod.
Click to expand...

Oh man I wished I knew before now. I bought a MC which is for a manual brake with disk brakes for my year model. I had to order it and it will be here in the morning. Do you think it will have the groove? They don't specify what bore size.
 
redfastback said:
get a 73-76 a body power disc master with a 15/16" bore. it will have a groove for your pushrod.
Click to expand...

OK

I went ahead and ordered a 75 Duster power disc master with a 15/16" bore. Both of the MC will be there tomorrow so I hope one of those will work.

Thanks.
 
When you put it together, put the rubber ring in the M/C opening first. Install the M/C on the firewall. Don't forget to bench bleed the M/C first. lightly spray the end of the pushrod with wd-40 or similar. Push it into the M/C. You might have to attach the pushrod to the brake pedal and use your foot to push it in. Next time to remove the pushrod, back off the nuts that hold on the M/C so they're flush with the end of the studs, and put a shim of some kind between the firewall and the M/C to shug it up. Go under the dash and with two hands yank back on the brake pedal really hard. Usually this will yank the pushrod and retainer out of the M/C. Why didn't you just use the new, aluminum M/C?
 
dusterdon said:
When you put it together, put the rubber ring in the M/C opening first. Install the M/C on the firewall. Don't forget to bench bleed the M/C first. lightly spray the end of the pushrod with wd-40 or similar. Push it into the M/C. You might have to attach the pushrod to the brake pedal and use your foot to push it in. Next time to remove the pushrod, back off the nuts that hold on the M/C so they're flush with the end of the studs, and put a shim of some kind between the firewall and the M/C to shug it up. Go under the dash and with two hands yank back on the brake pedal really hard. Usually this will yank the pushrod and retainer out of the M/C. Why didn't you just use the new, aluminum M/C?
Click to expand...

I really don't know why I didn't. I was just thinking a disk brake MC would work from the local parts house just as well I guess. I know that you have to buy a adapter for the aluminum one. Any advantages from the aluminum besides weight?
 
Well I finally got the right MC and it was the one redfastback told me to get.

Thanks.

I test drove the car and could tell that it stops much smoother now. It glides to a stop. I'm taking it easy at every stop so the pads will break in nicely. The crossed drilled rotors and the new wheels just set the car off. Now to move the leafs springs in and install the wheels in the rear.
 
remember your 30-30-30 test. 30 brakings form 30 mph to about 10, with 30 seconds in between each braking. then go easy for about 200 miles to temper the pads and rotors.
 
wait a sec!!! you were supposed to post pics of the new wheels!!!???? you didn't forget did ya? let's see 'em!!
 
redfastback said:
remember your 30-30-30 test. 30 brakings form 30 mph to about 10, with 30 seconds in between each braking. then go easy for about 200 miles to temper the pads and rotors.
Click to expand...

Yeah I have been doing exactly that. Sometimes I would throw it down in third and get down to 30 and then apply the brakes. LOL!

I got the right side leaf spring out and going to have to borrow a side grinder to remove the perch. My kit suppose to be here Tuesday so I then can reinstall everything, tack the perches on each side, and pull everything out to weld the perches good. Then I can get the wheels and tires on that I have.

Here are some pictures of the wheel,rotor,tire on the front. The wheel is dirty form the goop they use to put on the tire bead. One pic is with the flash and the other isn't.

Cuda boot area 016.jpg


Cuda boot area 017.jpg
 
cudaspaz said:
Hey ax', got any pics of the new master installed?
Click to expand...


Hey buddy.... I haven't talked to you in a while.

Yeah I've got a picture of it but it is just the old traditional stock version. I will throw in a picture of the little 273 as well. It's dirty and I'm not completely done with the engine compartment.

Motor 002.jpg


Motor 004.jpg


Motor 003.jpg
 
You must log in or register to reply here.
-

Back
Top