UPDATE on froze caliper

[egstandard04]

1985 Sporty with the Girling rear caliper. I can't get the piston to retract. I can get a rebuild kit from Harley for 60 bucks. Anyone know if that should fix it, or should I search for a new caliper? Retrofit options? I'm fixing this bike for someone else.

[egstandard04]

On further inspection, I took off the dust boot and pumped the pedal to get the caliper piston out quite far. The piston looks real nice, clean with no corrosion. I tried to push the piston back with a big C clamp, but it would barely budge. I then opened the bleeder and worked the C clamp and the piston went back in easily. I'm thinking maybe the rubber brake line has collapsed inside and won't let the fluid go back. Plausible idea? Opinions?

[ViennaHog]

Did you try to push the piston with the brake line connected? Sometimes the bottom valve of the master cylinder is blocked and the fluid cannot go back into the reservoir. Check it out.

[xlfan]

Check that master cylinder as said. How long since last brake fluid flush and change?

xlfan

[egstandard04]

I'm going to pull the line off at the master cylinder and see if I can get the caliper piston to go back in. If it does, that should tell me that the brake lines are ok and the problem would be at the master cylinder correct? Thanks for all your help, been a long time since I worked on an ironhead.

[ViennaHog]

Sounds like a plan. I bet it is the mc

[egstandard04]

Well, you guys were right. It was a totally gunked up master cylinder. Got it off, cleaned, bled the system with all new Dot 5 and it is working like a champ. Thanks a lot for all your help. You guys are great!

[ViennaHog]

Isn't it great when you actually fixed something without breaking something else?