Air in the Brakes

[Pyro Mike]

I have a 85 C-20 Camper Special I have replace all of the brake components and some twice excluding the metal lines and proportioning valve and I still get air in the system I don’t loose any fluid the master cylinder will overflow sometimes when you remove the top. It’s been bled an easy 30+ times by different folks and no one has a clue what to do not even the Chevy mechanics I have talked to.

[blue-streek]

uuuuuuhhhhhhhhhhh no idea :confused: wes mite know

[WES]

Something doesn't make sence. If your mastercylender overflows just by removing the lid, then somehow it is manufacturing fluid. I would replace the master cylinder and be sure to bench bleed it befor you install it. Then I would gravity bleed the system or have it bled professionaly. I know when you manualy bleed a brake system it can be easy to run it low on fluid bleeding the air out of the lines. Then you are inadvertantly introducing air into the lines yourself. WES www.ClassicHeartbeat.com

[WVtrucker]

That sounds like it could be a bad master cylinder. It doesn't make sense that the fluid should over flow unless it is sucking air in somewhere. Are all the bleeders tight? It could also be that there is a horrific leak somewhere that is sucking air back after the pedal returns.

Good luck with that.