The 1947 - Present Chevrolet & GMC Truck Message Board Network - View Single Post - Brakes sticking a lil do I have right prop. valve and adj. on brake rod?

DKN · 07-12-2010, 04:15 PM

If the caliper piston moved freely after the bleeder was opened that would suggest a problem between the caliper and the master cylinder. Somtimes the proportioning valve sticks, somtimes the hose or hard line become blocked in a way that holds pressure. If the caliper piston was still stuck after the bleed screw was opened then the problem is likley within the caliper. If the piston seal was in contact with engine oil it could swell and not allow to piston to move freely. If the seals were used with silicone, synthetic, or DOT5 brake fluid the rubber will swell slightly, and could cause the piston to feel stuck.

Danny Nix
CPP

07-12-2010, 04:15 PM	#39
DKN Active Member Join Date: Feb 2008 Location: Los Angles CA Posts: 136	Re: Brakes sticking a lil do I have right prop. valve and adj. on brake rod? If the caliper piston moved freely after the bleeder was opened that would suggest a problem between the caliper and the master cylinder. Somtimes the proportioning valve sticks, somtimes the hose or hard line become blocked in a way that holds pressure. If the caliper piston was still stuck after the bleed screw was opened then the problem is likley within the caliper. If the piston seal was in contact with engine oil it could swell and not allow to piston to move freely. If the seals were used with silicone, synthetic, or DOT5 brake fluid the rubber will swell slightly, and could cause the piston to feel stuck. Danny Nix CPP