Powercrapper

[progress1vebmx]

Ok, my powercrapper makes this weird clicking noise, coming from the pressure switch (it's new, grey one). It does it when I'm sitting at stop signs, lights etc. It also moves the pedal up and down on my foot and dims the lights. My brakes will feel very hard, and then i'll push though to get a spongy feel in the brakes that stop the car.

Should I just replace it with the vacuum setup?

 

[dan lephart]

powerrrrrrrrrr

Mine did the same thing. As I verified later it was the new type grey switch gone bad. It had been replaced under the original recall years ago. You could do the switch or the unit. Now you are stressing the motor too. I have a rebuilt unit I used a few weeks till I found a NEW GM UNIT for my show car. Professionally rebuilt with a new switch, master cylinder and accumulator. Check the parts for sale or
email onefastt@ameritech.net

Dan Lephart

PS. The jury is still out on conversions. I believe the GM engineers had the right idea.
PPSS Let the bull#### fly...

 

[progress1vebmx]

Ah, ok, so the switch could have gone bad even though it was replaced (possibly years ago). It makes that clicky noise constantly... and it stops clicking when I apply the brakes in. I'll have to try a new one of those.

 

[gofstbuick]

How clean is the brake fluid? I encountered a motor that would constantly run. Once I flushed the brake fluid and it was clean and clear, the motor stopped clicking. I do still see some peroidic small bubbles on the suction side of the reservior. I suspect that there is still some dirt on the seals of the power piston. I ordered a M/C rebuild kit and will rebuild the master cylinder this weekend. Though I want to do a pressure test on the unit to be sure that the accumulator pre-charge pressure is correct. Regarding the pressure test, the gauge assembly and adapter is available from Kent-more tools (licensed by GM) for $470. . I ordered a brake gauge kit from Harbor Freight Tools, $93. I then purchased a steel street tee (1/4 NPT with 2 female and one male ends). I had a machine shop convert the female 1/4 NPT to M12x1.5 (thread pitch for the accumulator and the pressure switch). The machine shop used a time-sert to convert the threads. I don't recomment using a helicoil to convert the threads, because of the pressures the powermaster motor generates. I ordered a adapter for the 1/4 NPT male to convert it to M12x1.5. Most hydraulic hose shops will carry this adapter and it is equipped with a steel gasket and rubber seal (that is hydaulic fuid resistant). The other female port is for the gauge. the adapter cost about $30 to make. Total $125 to be alble to test my powermaster unit. With the adapter, remove the pressure switch and install the adapter, remove the seal from the pressure switch and replace it with a brass gasket and install the pressure switch on the top of the adapter and hook the electrical connector back on to the pressurre switch. Finally connect the brake gauge to the female port of the adapter and start testing. The factory manual has very specific testing procedures regarding powermaster.