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Cheyenne Supr · 05-17-2008, 06:23 AM

Hey guys,
I found the problem and thought y'all might want to know what it was. All the parts I had were correct; shoes, wheel cylinders, push rods, springs, etc. I had already loosened up the cylinder bleed screw and pushed the rods all the way in, bled the lines, assembled and drove the vehicle, but the shoes locked up on the drum and would not release...I could barely get the drum off. I figured I had gunk in the brake lines and tried to vacuum bleed the system with 25 lbs of pressure, but I could barely draw any brake fluid so I knew something was wrong with my lines. At that point I began to take off lines one at a time and blow them out with 90 psi air pressure. What I found was the rubber brake hose at the passenger rear wheel had collapsed inside and was acting as sort of a check valve. It would let a very small amount of fluid out to the shoes, but nothing could return back through so the shoes would not release. The hose looked fine outside, but was almost completely plugged inside. With a new brake hose and clean steel brake lines it works like a charm!
Thanks for all your ideas. They did help me to brainstorm!
Larry

05-17-2008, 06:23 AM	#13
Cheyenne Supr Registered User Join Date: Dec 2003 Location: Nashville Posts: 48	Re: Rear Brake Problems Hey guys, I found the problem and thought y'all might want to know what it was. All the parts I had were correct; shoes, wheel cylinders, push rods, springs, etc. I had already loosened up the cylinder bleed screw and pushed the rods all the way in, bled the lines, assembled and drove the vehicle, but the shoes locked up on the drum and would not release...I could barely get the drum off. I figured I had gunk in the brake lines and tried to vacuum bleed the system with 25 lbs of pressure, but I could barely draw any brake fluid so I knew something was wrong with my lines. At that point I began to take off lines one at a time and blow them out with 90 psi air pressure. What I found was the rubber brake hose at the passenger rear wheel had collapsed inside and was acting as sort of a check valve. It would let a very small amount of fluid out to the shoes, but nothing could return back through so the shoes would not release. The hose looked fine outside, but was almost completely plugged inside. With a new brake hose and clean steel brake lines it works like a charm! Thanks for all your ideas. They did help me to brainstorm! Larry __________________ Larry 72 Cheyenne LWB Fleetside Oak Bed 350 w/ TH400 (finally complete!). 69 Chevy C-10 LWB 350 w/ TH350 (good 'ol rusty bullet proof dependable hauler). 02 Suburban Z71 4x4 (wife's driver).