Powermaster support thread!

[A2000RICH]

So what happens when the engine stalls and no more vacuum is made?

How about when the cheap one-way vacuum check valve fails and the booster looses vacuum?

How about when the vacuum booster fails?

I have had all that happen to me in the near 30 years of driving behind me.

I had the switch go bad - before the recall and I felt the pedal go from normal to semi-hard. When ya feel semi hard ya find a place to stop and try to see what's up. I kept driving it and it was just like any vacuum system that had a booster or vacuum hose failure.

So it seems the only maintenance is change the fluid - and that is a good idea for ALL brake systems anyway.

HEY RICH-------is the return key busted on your keyboard? I like reading your posts but it is not easy!!!!!!!!

sorry for the way i write----its just a old habit------i kind of write like i think----in bursts-----the number of dashes represents the time it takes for me to get the next thought............RC

 

[Robbie-87plz]

Had the PM fail on my GN one day, in heavy Honolulu traffic.
Pucker factor = 10.

 

[WLDWST]

Had the PM fail on my GN one day, in heavy Honolulu traffic.
Pucker factor = 10.

According to some pro PM believers ( not me obviously ), it's no big deal and you should have easily been able to stop if you were educated about the Powermaster and prepared yourself for this. You obviously panicked and should have kept your cool. You would have had at least 4 to 6 assisted stops to pull over. ( yeh right) This happened to me also, but when it happens to you personally it just plain sucks doesn't it? Buy a Vacuum system or Hydroboost and put the PM on a shelf where it belongs. My opinion of course, but then again like you said, pucker factor = 10 is hard to ignore.

 

[Blown&Injected]

According to some pro PM believers ( not me obviously ), it's no big deal and you should have easily been able to stop if you were educated about the Powermaster and prepared yourself for this. You obviously panicked and should have kept your cool. You would have had at least 4 to 6 assisted stops to pull over. ( yeh right) This happened to me also, but when it happens to you personally it just plain sucks doesn't it? Buy a Vacuum system or Hydroboost and put the PM on a shelf where it belongs. My opinion of course, but then again like you said, pucker factor = 10 is hard to ignore.

So what brake system will you go to when the vacuum fails or the engine stalls and the PS pump stops boosting the brakes?

 

[WLDWST]

So what brake system will you go to when the vacuum fails or the engine stalls and the PS pump stops boosting the brakes?

I already went with a modern design Hydroboost with updated braided lines and an aftermarket reservoir. It also holds between 15 and 18 lbs of boost easily. I am extremely happy although I would gladly use a good Vacuum system over a PM. I refuse to allow myself to fall victim to the unreliable, antique and outdated PM. If you all think it's ok, then go for it. There are those that will not take advice even though it is given out of concern for their safety. Just be aware that it can happen to you. No more comments from me on this thread.

 

[Blown&Injected]

I already went with a modern design Hydroboost with updated braided lines and an aftermarket reservoir. It also holds between 15 and 18 lbs of boost easily. I am extremely happy although I would gladly use a good Vacuum system over a PM. I refuse to allow myself to fall victim to the unreliable, antique and outdated PM. If you all think it's ok, then go for it. There are those that will not take advice even though it is given out of concern for their safety. Just be aware that it can happen to you. No more comments from me on this thread.

You must have missed my other post to this thread because it has happened to me.

I have been behind the wheel for about 30 years and I have had vacuum brakes go out on me and I have had the PM go out on me - it sucks to have ANYTHING go out on ya! --or should I say about vacuum boosters - "unreliable, antique and outdated" because it is more antiquated then the PM.

not gettin' mean - just makin' a point here...Lots of hose and fittings in them HB systems. I hope you do not have that system too long because it too will eventually fail and then I don't know what you will do for brakes - maybe by then they will have the perfect - never fail booster

 

["Turbo-T"]

This might start another Sh!t storm but when the hydroboost lets go you loose braking AND steering!
Ask me how i know.....

You mean as in a leaky hydroboost? One of our trucks at work (Ford 350 powerstroke) had a leaky hydroboost, left a trail of PS fluid down the firewall. Thankfully it never gave up the ghost while I was there.

So what brake system will you go to when the vacuum fails or the engine stalls and the PS pump stops boosting the brakes?

Manual brakes? They don't care if there's no vacuum or PS fluid.

 

[87GNSteve]

You mean as in a leaky hydroboost? One of our trucks at work (Ford 350 powerstroke) had a leaky hydroboost, left a trail of PS fluid down the firewall. .

This shot out from behind the fire wall it was sudden failure.

 

[turbofish38]

Manual brakes? They don't care if there's no vacuum or PS fluid.

It's still a pump with pistons and rubber seals. What the heck you going to do when it fails?

Personally I think you all are making a big fuss over nothing. Me? I'm Pro PM. There's a reason GM put them on the Turbo Regals to begin with but for most of us posting in these threads that's in way over your heads.

 

[Bent6]

It's still a pump with pistons and rubber seals. What the heck you going to do when it fails?

Personally I think you all are making a big fuss over nothing. Me? I'm Pro PM. There's a reason GM put them on the Turbo Regals to begin with but for most of us posting in these threads that's in way over your heads.

I agree - all types of brake systems have their issues and pros/cons - THEY CAN ALL FAIL!

I think the PM gets a bad rep - I'm not saying it's perfect but it's not the total POS some make it out to be.

I would unsubscribe to this one but I'm waiting to see some of RCs maintenance/rebuild tips as he seems to know more about it than anyone else. At least he seems to be willing to share info as long as the bashers don't turn him off.

 

[turbo nasty]

Just have an explosive charge on the driveshaft to blow it in half and drive it n to pavement when the brakes fail..LOL

I personally like the vac brakes from a cost and reliability aspect.

Cost..uhh alot cheaper than the PM

Reliability....vac has the the check valve, vac signal, booster and MC.
PM...fuse, pump, switch, hose, MC, accum, voltage.

Vac wins for me and "MY" situation

 

[87GNSteve]

It's still a pump with pistons and rubber seals. What the heck you going to do when it fails?

Personally I think you all are making a big fuss over nothing. Me? I'm Pro PM. There's a reason GM put them on the Turbo Regals to begin with but for most of us posting in these threads that's in way over your heads.

Why did GM leave it off the TTA?

 

[Alky V6]

Why did GM leave it off the TTA?

That's a good question. X2.

 

[Keller]

Maybe because they didn't even have enough room for the 8445 heads, let alone the PM motor in the F-body engine bay.

The only reason I don't have my original PM is because the unit blew the fuse halfway to the GS Nats years ago. I verified the problem after a fresh 30A fused blew immediately.

What'd I do? I drove it the rest of the way down. At a pretty good clip, too. I just knew I no longer had power brakes. Starting my driving career with a manual brake car, I wasn't bothered that much.

Now I didn't race it the moment I got down there. (The track wasn't open at 11pm, anway...) But the next morning I placed an order for a new Bendix PM at Auto Zone, and installed it in the hotel lot the following morning. Then I went racing. Its probably been in there 10+ years.

The original unit is in still in the Bendix box. I have a brand new motor from Hank Terry / Maval, and a GM rebuild kit on the shelf. Not to mention a few other spare units that others tossed around here and there. If I ever have another motor failure or seal failure, I will rebuild it and continue to use the PM.

Incidentally, I had already done the seal / piston rebuild on the original because of the factory advisory. I got ahold of the bulletin back in '91-'92 shortly after I bought the car, called in about it, and the person on the other end deemed that my car should get a rebuild kit. They asked "what dealer are you with". I explained that I was the owner, would be doing it myself, and was quite capable of it. They had a kit next-dayed out to me.

The PM "problems" most have come from ignorance and perpetuated idiocy. Ask any SCCA racer how often they change their brake fluid...

 

[87GNSteve]

Why did GM stop using them on the B body?

 

[Phoff]

No room under the hood of the TTA....

Pete

 

[87GNSteve]

No room under the hood of the TTA....

Pete

Plenty of room under the hood of the caprice why did they stop using them there?
I had a GTA I think there is enough room.

 

[Keller]

Perhaps the unit cost and the lack of maintenance done by grandpa and the Family Guy led to their quick demise from the '86 B-body wagons.

No one really reads replies here, do they?

 

[Phoff]

Why did GM go from the hydroboost to the Powermaster in 1985? No one knows...

Pete

 

[salvageV6]

Hey ALL kinds of brake systems won't work when you go racing and blow the lines off the rear with the line lock and starting line pressure, and then realize it at 114 mph at the big end.

Good thing it was the rear lines.

Happened twice to me, short line and the main big one the next track rental.

I guess I should blame the overpowered Powermaster system.

Even with the new lines in there I think the old rusty car will be track retired.

ANY brake system can fail, lines are very important to look at after 20+ years for sure, and are the main failure from what I've seen at least on GM cars over the long time I've owned them.

Just my .02, I bought the whole set. :biggrin:

PS: When it's below 0 degrees your powermaster motor can run for about a minute and a half with no issues, well a 15 year old slightly leaky one can anyway.