Joeypete

Hey guys. I just got my 86 Cruiser and it has the hydraulic brake booster instead of the typical vacuum booster. Is anyone familiar with these systems? I'm just wondering because I don't know what it's supposed to sound like. It makes noise like it's cycling or something and I don't know if that's good or bad. The unit actually looks very new...it's nice and shiny.

Thanks for you help!

joe_padavano

You have the Powermaster booster, which uses a small electric motor and pump right on the master cylinder to generate the hydraulic pressure for the power assist. This system was also used on the turbo Buick cars. It is different from the Hydroboost that uses the power steering pump as the source of hydraulic pressure. Many people confuse the two.

The noise you hear is likely the electric motor. If the system is working properly, the noise is normal. Be aware that the ball-shaped accumulator tends to go bad on these units, which could cause frequent motor cycling. The accumulator can be replaced pretty easily. It just screws on. One way to test it is to run the car and then shut it off. After an hour or so, press the brake pedal (with the car still off). You should have at least one pump of the brakes with power assist. If not, the accumulator needs to be replaced.

Joeypete

Cool, thanks Joe! Yer so smart I'll check on it today. Is it easy to find just the accumulator? I looked some up and only saw the whole unit listed...was damn expensive too! Thanks again for your help!

joe_padavano

Rock Auto lists the accumulator alone as A-1 CARDONE Part # 529702ACC, for the measly price of $255!!!

That explains why my friend with the GN has been scoring accumulators from the wrecking yard (late 80s FWD Caddys use them). It also explains why my 86 Caprice wagon (with 307 Olds) had the Powermaster replaced with a normal vacuum booster and master cylinder.

Joeypete

Wow that's expensive...I replaced the brake booster on my Toronado...took me hours but was actually pretty easy...just time consuming. Is the firewall setup to take the vacuum booster or did you have to drive holes?

joe_padavano

my 86 had the booster swapped before I got it, but there is no evidence of any drilling. Knowing GM, I'm pretty sure this is a bolt-in swap.

Olds64

My friend just bought a 63 Ford Galaxie and it has hydraulic assist brakes. He had to buy some parts for it and it cost him over $300. At least it is running correctly now. I like to go by the old adage of KISS! Knights in Satan's Service... er I mean... Keep it Simple Stupid. I will just stick with my vacuum assist brakes.

Joeypete

Ha...funny. I agree though. I may look into putting the vacuum power booster on it.