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Master Cylinder? Update!

Posted By: Dragula

Master Cylinder? Update! - 05/04/14 11:27 PM

Put Wilwoods on all four corners, now the brakes stick....What the heck can cause it....I am thinking the master cylinder had the seal baked out of it due to fender well headers, but with only a week and a half to go, I need consultation....
Posted By: racingblues1426

Re: Master Cylinder? - 05/05/14 12:08 AM

Did you check the length of the pushrod to make sure it isn't too long? That is my first guess.
Posted By: MR_P_BODY

Re: Master Cylinder? - 05/05/14 12:38 AM

Open a bleeder and see if it corrects it.. did you
center the caliper to the rotor
Posted By: Dragula

Re: Master Cylinder? - 05/05/14 02:09 AM

Calipers were all shimmed to center..and the brake pedal can still be pulled back further...This was a working setup when it had drums, so I am a little confused by this issue. If I tinker with the pedal, they all free up.
Posted By: Quicktree

Re: Master Cylinder? - 05/05/14 02:22 AM

did you remove all the old plumbing the prop valve etc? you need to get rid of all that and run a new style 15/16 master cyl
Posted By: Quicktree

Re: Master Cylinder? - 05/05/14 02:24 AM

take the plunger off and see if that releases it?
Posted By: Dragula

Re: Master Cylinder? - 05/05/14 02:35 AM

Quote:

did you remove all the old plumbing the prop valve etc? you need to get rid of all that and run a new style 15/16 master cyl



Prop valve is gone, one new AN03 line on each corner and the two off the master cylinder and the flex line to the rear axle
Posted By: Quicktree

Re: Master Cylinder? - 05/05/14 02:44 AM

one other thing to check is the black flex line on the rear especially if it is stock, they will fail inside not letting pressure release
Posted By: MR_P_BODY

Re: Master Cylinder? - 05/05/14 03:12 AM

Loosen the master a few threads and see if it still
does it
Posted By: cudatom

Re: Master Cylinder? - 05/05/14 03:57 AM

Dragula when I put Wilwoods on my Cuda in the late 80's I had the same problem. If you are using the stock MC there is a small pressure valve(that keeps a small amount of pressure on at all times for the drum brakes) that can be removed from the MC. I used a small screw put it into the seat(where the line for the rear brakes entered to MC)and wiggled the seat out. I removed the valve and bingo no more drag. I've had this set up since 1988. If you have an aftermarket MC not sure if this will help. Wasn't sure which MC you were using.
Posted By: Dragula

Re: Master Cylinder? - 05/05/14 11:43 AM

Quote:

one other thing to check is the black flex line on the rear especially if it is stock, they will fail inside not letting pressure release



Replaced that with AN03...
Posted By: Quicktree

Re: Master Cylinder? - 05/05/14 12:37 PM

nothing left but the master cyl, take the lines off and see if it releases.
Posted By: Dragula

Re: Master Cylinder? - 05/05/14 12:49 PM

Quote:

nothing left but the master cyl, take the lines off and see if it releases.



Ordered a new one along with the adjustable brake rod...I just don't get it though..
Posted By: Quicktree

Re: Master Cylinder? - 05/05/14 04:28 PM

Quote:

Quote:

nothing left but the master cyl, take the lines off and see if it releases.



Ordered a new one along with the adjustable brake rod...I just don't get it though..

like cudatom said there is valve for drum brakes in those master cly. either that or you lean so far to the right that it keeps pressure on the brakes
Posted By: Cab_Burge

Re: Master Cylinder? - 05/05/14 06:54 PM

All drum brake master cylinders have residual valves, usually around 10 lbs, in them somewhere, usually behind the brass seats that the brake lines hold in As already mentioned check that now by removing them with a # 8 sheet metal screw turn in 2 or 3 turns and then pry the seat out, the valves are rubber flapper valves with a small stainless spring inside the valves Remove them and throw them away and resaasembe the seats , make sure and crank down on the brake lines but don't strip the threads out of the master cylinders Same thing on the new matser cylinder also. On cars that have the master cylinders lower than the brake calipers you will need a 3 lb residual valves (Wilwood sells them )so the brake fluid won't drain back and overfill the master cylinders and leave air in the brake calipers
Posted By: Dragula

Re: Master Cylinder? - 05/06/14 03:02 AM

It was an after market master cylinder....Just got the new one todayoks identical...

Posted By: pittsburghracer

Re: Master Cylinder? - 05/06/14 03:12 AM

Strange = Mopar.
Posted By: Dragula

Re: Master Cylinder? - 05/07/14 03:24 AM

What if there was old DOT fluid still in one of the lines when I put in the Wilwood fluid?
Posted By: MR_P_BODY

Re: Master Cylinder? - 05/07/14 03:30 AM

Quote:

What if there was old DOT fluid still in one of the lines when I put in the Wilwood fluid?



If its not OLD(ancient) ... run it... or bleed that
line more
Posted By: Dragula

Re: Master Cylinder? - 05/10/14 12:34 AM

Well....How about reversed lines off the Master Cylinder!!!!!

Bingo!!!!!
Posted By: Quicktree

Re: Master Cylinder? - 05/10/14 01:44 AM

Quote:

Well....How about reversed lines off the Master Cylinder!!!!!

Bingo!!!!!

what do you mean
Posted By: Dragula

Re: Master Cylinder? - 05/13/14 03:31 AM

Well....Scratch the reversed lines... It was a lot more complicated than that...

Turns out $750 later....It was the weird angle the master cylinder was moved to so it would clear the fender well headers.

The brake rod was at such an angle, it wasn't able to fully engage or disengage...I was told I was super lucky I didn't have a real incident.
Posted By: Dduster

Re: Master Cylinder? - 05/13/14 05:41 AM

Good!! Brakes are really important as We all clearly know. Glad You found the source of Your problem.
Posted By: MR_P_BODY

Re: Master Cylinder? - 05/13/14 05:43 AM

Quote:

Well....Scratch the reversed lines... It was a lot more complicated than that...

Turns out $750 later....It was the weird angle the master cylinder was moved to so it would clear the fender well headers.

The brake rod was at such an angle, it wasn't able to fully engage or disengage...I was told I was super lucky I didn't have a real incident.



So how did you change the angle of the master
Posted By: Dragula

Re: Master Cylinder? - 05/13/14 11:54 AM

That is where $750 comes in handy, as well as someone who can weld. Maybe I can get a picture.
Posted By: racingblues1426

Re: Master Cylinder? Update! - 05/13/14 07:47 PM

I had a feeling you'd find that the rod was the culprit. Been there and done it. Hope all else works out and you go kick some x brands butts.
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