Brakes dragging

[molinerat]

Bought a 61 impala with disc brake conversion on all four corners. Brakes work good for the first few miles. After about 4-5 miles of driving they start dragging and get tighter and tighter until it's a struggle to drive. Afro t and rear doing the same thing. Stop driving for about 45 minutes and let the car sit and cool off and the brakes will release. Any ideas what I have going on? At my wits end. Thanks in advance. [S

 

[21willys]

It probably still has the master cyl for drum brakes.

Are the reservoirs for the front and back the same size? If so it's a drum master cyl.

 

[molinerat]

Rear reservoir looks to be a little smaller

 

[RPM]

Check the linkage from the pedal to the master cyl. There needs to be some play in the rod. It cannot be tight at all. This could keep the piston partially down in the bore and not let the fluid return to the master. I have seen this more than a few times.

 

[molinerat]

I have checked that. It was too tight and adjusted and it seemed to help a little. May put a little more end play in it to see if it helps.

 

[sgtpontiac]

Sounds like you are on the right path if it helped.....otherwise I was going say the same as 21willys....drum Mc on a disc set up....

 

[molinerat]

It looks like a corvette style master with 7" booster

 

[UncleDonnie]

You may want to flush the fluid cause if there is water from condensation it will expand with heat.

I have also had the rubber lines come apart inside and play one way check valve not letting the calipers release. Fried new brakes on the tow rig. Now if I do brakes I do new lines and the best are braided stainless, firmer pedal.

Don