80' Phoenix Caliper wont retract

[dana]

Hello, our 16 year old found a 1980 Phoenix that had less than 80k miles on it for less than a grand so she bought it. After a water pump, pads, calipers and rotors we still cant get the drivers side caliper to retract.

The passenger side is fine.  When the car is on stands and in drive the rotors are turning true, no wobbling, which is hopefully telling me the hub is running straight.

When the brakes are applied the drivers side caliper, which is brand-new, wont retract back unless I open the bleeder valve. When I open the bleeder valve the caliper retracts and the wheel hub starts spinning normally.

Can anyone please give me some insight on what the problem may be? The caliper is getting plenty of fluid on the bleed but just isn't retracting. 

Thank you,
Dana

[TWO LANE BLACK TOP]

Sometimes the rubber hose running to the caliper from the hard line collapses on the inside...Will look normal from the outside...Doesn't allow the pressure to release from the caliper...When the brake pedal is depressed the pressure holds the line open... When released there is no pressure to hold the line open...So it closes up..Won't allow the fluid to escape from the caliper...Would suggest replacing both the soft lines running to the calipers.......

Edited May 16, 2018 by TWO LANE BLACK TOP

[Frosty]

2 hours ago, TWO LANE BLACK TOP said:

Sometimes the rubber hose running to the caliper from the hard line collapses on the inside...Will look normal from the outside...Doesn't allow the pressure to release from the caliper...When the brake pedal is depressed the pressure holds the line open... When released there is no pressure to hold the line open...So it closes up..Won't allow the fluid to escape from the caliper...Would suggest replacing both the soft lines running to the calipers.......

Agreed. I owned a '81 Phoenix back in the mid-80s. This was the Citation platform - the new "X" platform and GM's first mass produced FWD car platform.

As Two Lane explained, the rubber flex line from the hard line to the caliper is a line within a line. That inner line collapses and won't allow fluid through. Therefore the flex line should be replaced - and as Two Lane suggests, both should be replaced for insurance/peace of mind purposes.

In my case, the shop tried to clear the original line by trying to apply 320 pounds of pressure and it didn't work. So now you know that replacing them is what you need to do.