Hi,
So i recently did a diff swap, but the dif had to be rebuilt, so the car sat apart for 2 weeks. I went to put the car back together, and i cant put the drums back on :( neither side. The adjustment screw is screwered in all the way. The piston seems to easily move when i press it with the screw driver, but the drums just wont go on. Any ideas of whats going on and how to proceed?
Crack the bleeder screw open a bit, and make absolute certain your parking brake isn't on/hung up. Some brake fluid will leak out and it will eat up the paint. Bleed the brakes afterwards
Quote from: metallicareload99 on May 13, 2018, 12:10:06 PM
Crack the bleeder screw open a bit, and make absolute certain your parking brake isn't on/hung up. Some brake fluid will leak out and it will eat up the paint. Bleed the brakes afterwards
Ok, thank you, ill try that.
The one weird thing is that the the cylinder does move fairly easily when i push on it... so weird why i can compress it easily...
Ok guys, i give up... the hand brake is not on, i undid the bleeder a bit, tried to wiggle and squeez and nothing... the mechanics of things look legit, dont see any issues, everything is nice and tight.
Can i take out adjustment screw and drive the car to the shop?
Quote from: euroZ06 on May 13, 2018, 11:46:35 AM
The piston seems to easily move when i press it with the screw driver, but the drums just wont go on.
Do you mean the piston in the wheel cylinder? The return springs on the shoes should have both pistons pushed back into the cylinder with the top of the shoe pressed hard against the backing plate stud.
You can't remove the adjuster and drive the car; the adjuster is the lower pivot for the brake shoes.
Try backing the parking brake adjuster all the way off and see if the shoes will retract enough to install the drums, then readjust.
You said you did a diff swap, are the backing plates the same, your old one could be 10" and the new diff could have 11".
Quote from: John_Kunkel on May 13, 2018, 03:59:53 PM
Quote from: euroZ06 on May 13, 2018, 11:46:35 AM
The piston seems to easily move when i press it with the screw driver, but the drums just wont go on.
Do you mean the piston in the wheel cylinder? The return springs on the shoes should have both pistons pushed back into the cylinder with the top of the shoe pressed hard against the backing plate stud.
You can't remove the adjuster and drive the car; the adjuster is the lower pivot for the brake shoes.
Try backing the parking brake adjuster all the way off and see if the shoes will retract enough to install the drums, then readjust.
Just wanted to point out that i didnt remove anything when i did the instal, i just removed the drum to pull out the axels.
The pistons are not pressed in, i can easily move them with the screw driver.
Ill have to try this another day and follow your steps... i just cant figure out what went wrong, since i didnt take anything apart... and the issue is on both sides. All the springs seem to have tension on them, everything seems to be in the right place...
The pistons should be compressed by the brake shoes spring tension, and if you can compress them they should stay in. If they come back out then somethings not assembled correctly.
Is it possible that since Im sure you have the rear housing hanging at full travel, the e-brake cables are now stretched possibly pushing the shoes out?
Try jacking up the rear assy till you can lift the whole car (fully compressed suspension) and then try to put drums on....
Open up the bleeders, stick a hose on that fits the bleeders empting in to a can. Put a nylon ratchet strap around the shoes, both driver and passenger side and tighten them down, see if shoes compress, measure the shoes outside diam. then measure the drums ID, just to see what the difference is if any. Wait, you can't get the drums on from the start or drum starts but won't go all the way. Any chance you put 3'' wide front shoes on the rear?
Got a picture of the brake hardware?
Solved. I did some bleeding.
Something is not right. You do not have to bleed the brakes in order to install a drum.
:iagree: Possibly the pedal pushrod is adjusted too long and causing pressure to be trapped in the system preventing the shoes from fully retracting.
Quote from: John_Kunkel on May 16, 2018, 03:33:02 PM
:iagree: Possibly the pedal pushrod is adjusted too long and causing pressure to be trapped in the system preventing the shoes from fully retracting.
Perhaps, but if the drums slid off and nothing else was disassembled, they should have slid back on the same. And if the pushrod was holding them, the brakes would be dragging terrible while driving if they are out so far that the drum wont fit and shoes are seized.
Well, if bleeding solved the problem, trapped pressure in the system was holding the shoes out. One way pressure could build up in the system (temperature change) and not simply dissipate through the MC reservoir return port is if the return port is blocked and that's commonly caused by a pushrod that's adjusted too long.
But how were the brakes bled with the drums off? What procedure was used? He said he had already opened the bleeders prior and the shoes didnt retract any. Opening the bleeder alone would confirm or rule out a master cylinder.
Someone could have installed a residual pressure check valve. Holds 10psi line pressure for drum brakes. They use them with aftermarket master cylinders. IE Wilwood. Holds the shoes against the drums for less pedal travel
The shoe return springs will definitely overcome the 10 psi RPV as long as there is a return path to the MC reservoir.
Sorry for late reply on this.
Problem was this idiot right here. I was putting the adjuster in the wrong place. Dumb error.
Don't feel bad, I've been doing it for over 50 years and I often have to look at a picture to see how it goes together.