Brakes ?

[Brian Mac]

Front disk brakes (both sides) locked up the other day. Have been using the car for last 2-summers after complete restoration. Pedal was hard with no travel, once I backed off break line at master the calipers released.

Have removed master cylinder, no sign of scoring or issue inside, rubber boots are good condition.

 

Anyone else have had this happen? Any thoughts?

[datzenmike]

Check pedal free play. This is pedal travel before resistance is felt. Usually a few mm or 1/16" or so. If the master push rod can't fully return to rest position, some pressure can be trapped ahead of it. Each time you brake more is added until the pistons are locked.

[Tacomaboy-1]

Aswell make sure your brake light switch is adjusted correctly. Having heavy contact between switch and brake pedal arm can cause brakes to heat up and drag.