So, I got the wagon going yesterday. Felt good to drive her again. One of the major problem. The brakes are hard as hell. Seems like no power at all. It barely stopped when I parked at work. Then again when I pulled in to park. Had to hurry and put her in neutral to keep her from jumping the curb. New master, brake booster, and front brakes within the past few years. Another big thing is the idle it is way high. it is not on choke. you need to really hammer the throttle to get it to idle normal. Not even touching the idle screw. I can force it but jumps back to high idle. Tim
Sounds like the booster is bad. Sometimes the master cylinder leaks out the back in to the booster and kills the seals? Just a thought, but I would check the booster first. With regard to the high idle, try some carb cleaning spray on the outside of the carb first...
my manual brakes were horrible when I first started driving my 66. Couldn't get hardly any brake action at all. Replaced a bunch of parts, adjusted things....turned out to be a collapsed hose to the rear brakes and all was good.
Bad booster. Block off the vacuum to the booster and see if the idle lowers. Might be a vacuum leak in the booster.
Here is a link for some simple tests. Similar to what is in the Buick Chassis manual. http://mbmbrakes.com/brake-booster-diagnostics/
Booster issue. Check the hose from the booster to the intake manifold. If that is ok, your booster is most likely leaking vacuum. You may be able to hear a hissing sound near the source of the leak (possibly from under the dash near the brake pedal)
I had a power brake booster check valve malfunction once, took me a long time to find the problem. Ten dollar part.
