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Master Cylinder Frustration

It's nice to know that I am not the only one with this issue! Did you use DOT5 also? Let me know how it works out for you.
P.S. I sure wish it was a 62-65 2dr post Mopar!!......not a Chev!
Good Luck With Yours Tomorrow!!
Got the new one in yesterday works fine and did not leak..........However I am only able to get fluid to the left front wheel. Probably need to put in new lines.
 
Got the new one in yesterday works fine and did not leak..........However I am only able to get fluid to the left front wheel. Probably need to put in new lines.
That's not good. I'm not being a smart ***, just asking.... you did bench bleed before installation?
 
Got the new one in yesterday works fine and did not leak..........However I am only able to get fluid to the left front wheel. Probably need to put in new lines.

If it's a used wheel cylinder, the bleeder could be closed off with dirt/rust. Remove the whole bleeder to check.

If it has used brake hoses, they can come apart on the inside and block the flow.

Used steel lines can be rusted shut.
 
That's not good. I'm not being a smart ***, just asking.... you did bench bleed before installation?
Yep bench bleed and it is not leaking and working fine for the Left front, all the wheel cylinders are new.
 
If it's a used wheel cylinder, the bleeder could be closed off with dirt/rust. Remove the whole bleeder to check.

If it has used brake hoses, they can come apart on the inside and block the flow.

Used steel lines can be rusted shut.
New lines next for the rear and right front hose, hope that solves the issue.
 
Nothing wrong with a 59 2 door post pretty rare I assume.

I just had/have the same issue with my 65 Coronet.
Redid everything and stepped on the brake pedal a few times and it leaked between the cylinder and the booster just like the old one did before I redid everything. The same cylinder seals as you?
Picked up a rebuilt one from Autozone and it looks like a really well built unit. The other one was from Advance. Both have the same part # but look different fit and finish wise. I'll change them tomorrow if it gets below 100*

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The tab holding the piston in the mc is a shipping tab only. Don’t use that in the vehicle, it will bend out and allow the piston to extend causing a leak. Happened to me before. Needed a collar with seal that bolts to both rear threaded bolt holes.
 
The tab holding the piston in the mc is a shipping tab only. Don’t use that in the vehicle, it will bend out and allow the piston to extend causing a leak. Happened to me before. Needed a collar with seal that bolts to both rear threaded bolt holes.
Damn!!!!!!!!! now I have to remove it again. I did not know that, but it makes seance.
 
Damn!!!!!!!!! now I have to remove it again. I did not know that, but it makes seance.

I had to make a flange out of steel as my original was missing.
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Right front hose was completely blocked could not even get air through it.
I did find the flange and screws on another one that I had extra but the rubber cover was not good.

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Thats the Brakes!

The boot is just a dust cover. You can probably find one at NAPA. Just measure it.
 
Thats the Brakes!

The boot is just a dust cover. You can probably find one at NAPA. Just measure it.
No boot necessary, tried a test fit and that flange and screws do not go to this application. Going back to the tiny clip, seems to work fine with it on. Or maybe remove completely.
 
No boot necessary, tried a test fit and that flange and screws do not go to this application. Going back to the tiny clip, seems to work fine with it on. Or maybe remove completely.
I wouldn't remove the clip unless it has a C-clip inside the bore to keep the cylinder from coming out.

The dual master I bought didn't even have bolt holes for the boot flange. Drilled my own holes to install that and the boot and return spring. Mine had the C-clip.
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No boot necessary, tried a test fit and that flange and screws do not go to this application. Going back to the tiny clip, seems to work fine with it on. Or maybe remove completely.

Just remembered you have power brakes :realcrazy:
 
No C clip so I put the shipping clip back on.
Turns out the rear brake hose is clogged as was the right front one also. Got the rear hose off but twisted the metal line off.
All the lines are clear now and I will try to double flair the rear one that twisted off.
Ordered a rear hose from Autozone $11.99 NAPA $14.49 + shipping from Ohio.
Back at it tomorrow.
 
So I picked up my third master cylinder at Napa a short time ago ( this time a rebuilt), because the last two New ones, would leak past the piston on the bench bleed. Much to my surprise I find , (for the first time) in the box, an ATTENTION notice that states .."When bench bleeding this master cylinder, do not depress the piston more than one inch. Doing so will give the appearance of the unit leaking". This information did not appear in the last two cylinders that I purchased. This is a single type reservoir system, non Mopar, and quite frankly is a re- education for me. I must have forgotten the one inch rule! So in the spirit of the idea behind this site ,I am passing this on because it gives you one more thing to consider , or one more question to ask, if you ever run into the same problem bench bleeding an old style single master.
I intend to follow this guidance to see if the third time is a charm!
Thunder
 
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So I picked up my third master cylinder at Napa a short time ago ( this time a rebuilt), because the last two New ones, would leak past the piston on the bench bleed. Much to my surprise I find , (for the first time) in the box, an ATTENTION notice that states .."When bench bleeding this master cylinder, do not depress the piston more than one inch. Doing so will give the appearance of the unit leaking". This information did not appear in the last two cylinders that I purchased. This is a single type reservoir system, non Mopar, and quite frankly is a re- education for me. I must have forgotten the one inch rule! So in the spirit of the idea behind this site ,I am passing this on because it gives you one more thing to consider , or one more question to ask, if you ever run into the same problem bench bleeding an old style single master.
I intend to follow this guidance to see if the third time is a charm!
Thunder
The one I got from autozone did not state the one inch issue but the one from Advance did.
I did maintain the 1" directions on both but the Advance one leaked and the Autozone one did not.
Both were the same part # but looked totally different visually, Autozone one looked professional and the Advance one was already rusting two days after I installed it.
On another related issue..... My rear brake hose was clogged beyond use. Autozone $11.99 Advance $12.49 NAPA $14.49 + shipping from Ohio. The main reason I do not buy much from NAPA. Federated (fisher auto parts) guy just laughed and said you are going to spend the weekend working on a 65 Coronet!!! Probably a chubby guy.
See you at Carlisle ???
 
The one I got from autozone did not state the one inch issue but the one from Advance did.
I did maintain the 1" directions on both but the Advance one leaked and the Autozone one did not.
Both were the same part # but looked totally different visually, Autozone one looked professional and the Advance one was already rusting two days after I installed it.
On another related issue..... My rear brake hose was clogged beyond use. Autozone $11.99 Advance $12.49 NAPA $14.49 + shipping from Ohio. The main reason I do not buy much from NAPA. Federated (fisher auto parts) guy just laughed and said you are going to spend the weekend working on a 65 Coronet!!! Probably a chubby guy.
See you at Carlisle ???
This Parts thing can be a serious pain in the ***! The master I picked up today doesn't leak when bench bleeding ....but now the piston sticks inside, and only returns if it feels so inclined! Ordered yet another!
Sorry won't be fitting Carlisle into my budget this year! Burned up my Fuel budget going back and forth to Napa! LOL
 
So I finished everyting on the brake system, had the wife help bled the brakes and now the new new MC is leaking.......WTF?
 
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