<VV> brakes and master cylinder

[Ernie Sanders]

Several years back I bought a 55 chevy with single master cylinder non power brakes.  Got it out and noticed after a good run of 15 minutes the brakes were hard but not stopping.  Discovered the drums were hot.  Talked to my mechanic buddies.  At their suggestion I changed the brake hoses an axle at a time.  No help.  Then changed the rear block, no help.  Rebuilt all the cylinders, no help.  I was very puzzled.  Went into the master cylinder.  It all looked good but, wait, I noticed the small hole in the bottom of the reservoir was not there.  Finally took an ice pick and scraped around and finally scraped enough material away to reveal the small hole that was severely plugged up.  Got it cleaned up, bench bled it and all was good.  The function of the hole is to relieve the pressure after the brake pedal is released.  My brakes would build up pressure and not release for a long time.  That's why when I'd get into the car after a few hours I had brakes
 again.  This took several weeks and several dollars to discover the answer.  You might want to check the master cylinder.  Ernie in Louisville.