howardjm

First of all I am a first time Corvette owner and am trying to do all work myself, this forum has gave me excellant advice and appreciate all the input. Now I have another problem on my 89 Coupe. Here are the sequence of events prior to installing new front pads.
1. I pulled the wheels and pressure washed the front suspension
2. Replaced front shocks
3. Installed new brake pads
4. after I installed the pads I started the vehicle and pumped the brakes.

Now the brake pedal takes excessive force to stop the vehicle. I also here a air noise when I apply the brake. At higher speeds It feels like the stopping is normal, however at lower speeds I have to push hard on the pedal. I did not, as far as I know get air in the system, meaning I did not open a brake line or let the master cylinder get low, I have no leaks and the Master cylinder is topped off. Do I need to bleed the brakes? I did not hear the air sound prior to any of this. Please help!

Analog Kid

It sounds like you have a cracked vacuum booster. They are prone to cracking around the check valve, but it could be anywhere.

zr1fred

Disconnect the vacuum line to the booster and plug it. See if the pedal feels the same. Inspect the booster carefully. Sometime if they've had a bad master cylinder they will leak into the booster causing it to slowly rot out, too.

howardjm

do i plug the booster or the vacuum line?

AirForceOne!

[QUOTEDo I need to bleed the brakes?][/QUOTE]

Yes! You should also consider flushing the brake system too!

zr1fred

You remove the vacuum from the booster, and seal the vacuum leak generally by plugging the line. Generally air in the brake lines won't cause hard pedal, and unless you opened the lines or have a leak in the lines (system) you shouldn't have air in them, or need to bleed them, at least for a hard pedal problem. You might check to make sure the new pads are not sticking in the calipers, and the calipers are not sticking, if the problem started as a result of your work.