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73-87 Chevy _ GMC Trucks => 73-87 Chevy & GMC Trucks => Topic started by: dirtriderdd on October 07, 2017, 08:24:31 pm

Title: Hard Brake Pedal
Post by: dirtriderdd on October 07, 2017, 08:24:31 pm
Brakes were working fine all day yesterday.  Then immediately upon start-up for my drive home the brake pedal went hard.  I have brakes but completely unassisted.  I have vacuum coming off the engine to the booster, but I don't know exactly what pressure.  The brake pedal does not compress when I turn on the engine.  Leads me to think it is a bad booster.  I changed the booster today, but still have a hard pedal and no assisted brakes. I thought for sure it was the booster.  It's possible the new (refurbished) booster is bad, but unlikely.  Any suggestions? 

Title: Re: Hard Brake Pedal
Post by: VileZambonie on October 08, 2017, 07:12:39 am
When you pull the check valve out of the booster do you hear the vacuum seal break and a whoosh of air?