powermaster problems help

[GNcincy87]

i have a stiff brake pedal and it will not push down...will not stop the car it has hardly any holding force.. anyone know what i should check? i tried the directions on the accumulator ball that said pump the brakes 10 times with the ignition on but car not running...well the line wouldnt crack to bleed it its froze and just rounds the head off...so i duno if thats the problem or not.. can anyone help me out..thanks

 

[1quick6]

Probably best to provide more detail:

Is the powermaster motor running at all? I assume the brake warning light is lit.

What were you trying to do when you were "cracking the line?" If you were just trying to bleed the accumulator, there isn't any need to disconnect anything. You only need to disconnect the brake lines when bench bleeding the master cylinder.

At this point, take a step back and troubleshoot the system logically. Here's a good start -> http://www.gnttype.org/techarea/brakes/brakespage.html

Let us know what you find out, but there are key details we need to be able to help you.

 

[GNRick]

Probably need a new accumulator. If I were you I would check prices for a whole new PM as they come with a lifetime warranty. Someone posted a link to one from Amazon.com for around $350. That's a great price. Would also check autozone. Last I saw, Kirban was still asking around $600 but you could check with him too. Even if it is just the switch, that would set you back around $100 I believe. Air in the brake line would not cause a hard pedal.

 

[HI85WH1]

Based on my experience, the acumulator failing symptom is rapid cycling of the PM as the unit tries to rebuild pressure.

Too much of this and the motor/pressure switch will fail, causing high pedal effort and inability to stop.

Options:

1) Order a reman Powermaster and replace
2) Covert to Vacuum using parts from another G-body + change the billet vacuum block
3) Convert to Hydroboost

OF these 3 choices, IMHO the conversion to vacuum is the least expensive, but you will need the pedal assembly from the donor car (or at least the pedal and all the little pieces)

Hydroboost systems can be pieced together by using OE parts from diesel powered G-bodies and splicing in the low pressure side. Discussions here will give you part numbers that you will need... and you can utilize the existing pedal.

Replacing the PM is the straightforward method... but pricey.

 

[GNcincy87]

Thanks everyone for the help. i think the motor is shot. everytime i put a new fuse in it just blows. ive checked all the wires, ground exc and everything is right. i do have an original acdelco motor for the powermaster never used still in the box, but ill prob sell it to somebody that has a low mile original car that can benefit from it.. what would that motor be worth? any ideas?? its oem brand new and when i bought it i was told it was one of the last ones available. is that rare or are they still out there? i think ill be switching over to vacuum or hydraboost. im still unsure on which one

 

[1quick6]

I don't know what to tell you on the price of the new oem motor, but I am sure its selling price should cover a vacuum or hydroboost conversion. Honestly, if you aren't concerned about originality on your car there really isn't a good reason to delay a conversion. As soon as you replace your motor, you might have the accumulator ball fail or something whacky. Powermaster can work well if taken care of, but we all know that every part that fails is expensive!