Hi!

I have a 79 Coronado, which here in Argentina, is basically a 225 Slant Six.

Recently, i put a new mast cylinder and changed the booster valve ( the plastic ) since the old one had a crack on it. Checked the hose that goes to the intake manifold vacuum.......all ok.
The problem is that the brake pedal gets HARD on start, then when the car is running, it's SOFT. But for example, when i have to apply the brakes on a stop, and then shift again to 1st gear.......AGAIN.... the pedal gets really HARD.

I supposed a problem related to the booster, since it's an intermittent problem.

Could be a problem on the booster valve, should i check the hose ???

Or the problem could be in the booster diaphragm ???

Should i inspect the booster for leaks ??

Could it be the 6th piston... suffering of compression-leak ??.... But i'm in doubt about that last....


What do you think ??

Besides the coronado, i also have a 71 Camaro !!

MANY TX!!!!

Sounds a lot like a bad (leaky) booster.

_________________
一期一会
Too many people who were born on third base actually believe they've hit a triple.