Brake Calipers Sticking

[AH619]

I Thought I Would Pass This Tidbit Along.
When I Built Coppertone I Used A New Booster,rebuilt M/cyl,calipers And Slave Cyls. New Rotors/drums And Hardware Kits On The Rear. I Replaced Any Lines That Werent Perfect.
Anyway When I Started Driving It My Calipers Would Start Dragging. I Would Have To Release A Bleeder Screw To Free Them. So I Thought I Had A Bad Caliper. On Goes 2 New Calipers. Same Problem.so Now Im Thinking Proportioning Valve Since Thats All That I Reused.pulled One From A 2 Wd That I Know Was Good. Had To Replace Master Cyl To Get Brake Lines To Match Up. Anyway After Another $100.00 Or So Im Back Togather. First Drive Ok Then On A Longer Trip Found That My Problem Has Moved To The Rear Brakes. Now Im Really Scratching My Head. I Posed This On This Site And Didnt Get Anywhere, I Asked Everyone I Came In Contact With. Finally An Old Dozer Mechanic Came In One Saterday And Was Admiring My Truck. I Told Him About The Problem He Said My Push Rod Was Too Long. He Said To Grine Some Off And It Will Let The Fluid Return Into The Master Cyl. Instead Of Grunding I Installed 2 Fibre Washers To Space The Cyl From The Booster Because With My Luck I Would Grind It Too Short. Anyway This Fixed The Problem. 2, 3cent Washers And 10 Minutes Fixed This Head Scratcher. Hope This Helps Someone Someday. Marvin

[red71cheyenne]

Good to know, Thanks for posting it. I'm sure someone will use the info.

[lowriden58]

man i had this problem about 6years ago and could never figure out what was wrong i spent more money on trying to figure out what was wrong then the truck was worth

[steelhorse]

Sorry I didnt see this sooner I could have saved you some trouble.The first time I saw this I chased it a while.

[Longhorn Man]

steelhorse... you took the EXACT words out of my mouth. I knew what it was with mine when i had this issue though, becouse I had just replaced my master cylinder and it came with insturctions and it mentioned this.
However, you shouldn't have had to grind on anything... the pushrod is adjustable.

[cljimmy72]

Thank you for steering me in the right direction. I had the same problem with my brakes staying on. I thought it was only the fronts so I replaced the front calipers thinking they had frozen with no help. I tried shimming the booster and adjusting the rod with no fix from what I read from this thread. To make a long story short it ended up being a double seal between the master cylinder and the booster. A cup shaped seal supplied with the master cylinder and a flat seal provided by my newly rebuild and plated booster. There is room for only one seal not both therefore this kept the brake fluid from returing to the master cylinder. Thanks again for your help. I was looking toward the proportioning valve as my problem also.

[Sport/Truck]

Originally Posted by Longhorn Man

steelhorse... you took the EXACT words out of my mouth. I knew what it was with mine when i had this issue though, becouse I had just replaced my master cylinder and it came with insturctions and it mentioned this.
However, you shouldn't have had to grind on anything... the pushrod is adjustable.

AH619- Can you try adjusting the rod on your break peddle and see if thats also fixes your problem? When you mentioned rod thats what came to my mind.
Glad to hear you got this figured out none the less.
s/t

[fastom]

I just had the same issue, small world!
http://67-72chevytrucks.com/vboard/s...d.php?t=294877