Power master accumulator ball volume
- Thread starter PaulRV6
- Start date
Welcome!
By registering with us, you'll be able to discuss, share and private message with other members of our community.
standupjskiguy
Member
- Joined
- Mar 18, 2009
- Messages
- 237
I have one and it works fine. It may consume a bit more fluid so make sure the reservoir is full before turning on the key
or it'll suck air as it gets to the bottom.
or it'll suck air as it gets to the bottom.
Saying to "fill" the reservoir is somewhat misleading. Here is a picture of the correct fill levels WHEN the system is discharged by the appropriate key off, 10 pedal presses.
Take note of the stepped fill gauges inside the reservoir in the following two pictures!!!!!!!!!
Take note of the stepped fill gauges inside the reservoir in the following two pictures!!!!!!!!!
Mrneg9
Get Some !
- Joined
- Feb 10, 2008
- Messages
- 431
Yeah if you fill it to top with out properly doing the correct routine you will find a large puddle of brake fluid on your floor.
Ok guys I put the new accumulator on and cleaned out the reservoir and put in fresh fluid. It works slightly different but I still have a problem. I'm wondering now if I spent 200.00 for nothing. Here is what it is doing:
After the pump drew down the reservoir the pump shut off (less than 20 secs) I pushed on break pedal and travel seemed to be excessive and pump turned back on. Turned key off and let it set.
Turned key back on and no brake lite and no pump running. I push down on the pedal and travel is excessive but no pump and no lite, the second time I push the pedal the pump comes on but no brake lite. Each time the pump runs it is about 15-18 secs. It is sucking down the reservoir like it should.
What should I do next?
paul
After the pump drew down the reservoir the pump shut off (less than 20 secs) I pushed on break pedal and travel seemed to be excessive and pump turned back on. Turned key off and let it set.
Turned key back on and no brake lite and no pump running. I push down on the pedal and travel is excessive but no pump and no lite, the second time I push the pedal the pump comes on but no brake lite. Each time the pump runs it is about 15-18 secs. It is sucking down the reservoir like it should.
What should I do next?
paul
Daniel PErkins
Member
- Joined
- Oct 5, 2013
- Messages
- 56
Paulrv6---are you sure you have all the air out of the system? I bled my brake several times after completely rebuilding my brake system with new wheel cylinders, new hoses and rebuilding the calipers--pedal felt spongy. I then used a Phoenix reverse brake bleeding system where you start at the right rear brake and force fluid up to the master cylinder--I had my brake bleeding assistants--er-wife watch and report at the master. Bubbles appeared on all four corners using this system. Brake pedal felt 10 x's better afterwards. I am confident that mine had air in the system. It sounds like yours still may have air. What type of proprortioning valve is in your car. Some were brass others were cast iron and prone to suck air into the system. They sell brass replacements on hiway stars and other venders on this forum. You may need to do more in-depth powermaster diagnosis regarding pressure. Search the powermaster thread on diagnosis. I used the kent-Moore powermaster pressure gauge on mine to make sure pressures were within specs. Hope it helps. Dp
Dan, I hear you about air being in the system but I did nothing to get air in in the first place, unless you can get air in from sucking out the reservoir and wiping it dry before refilling?
I would like to be able to check actual pressures but without a test kit I can't. I was thinking about constructing one but not sure how it is setup. How much did the one from KentMoore cost? It just feels like the pedal is going down too far but I never did anything to affect that. This is why I am miffed. Thanks
paul
I would like to be able to check actual pressures but without a test kit I can't. I was thinking about constructing one but not sure how it is setup. How much did the one from KentMoore cost? It just feels like the pedal is going down too far but I never did anything to affect that. This is why I am miffed. Thanks
paul
Here is what I found out today. When I turned the key on, no brake lite and no pump running. Pushed on brake pedal and pedal went down to floor with very little resistance. Pushed pedal down the second time and pump ran and I could push pedal just about down to floor with some resistance, no brake lite. I didn't do anything to the brake system to cause the pedal to almost go down to floor. Should I buy a tester?
I have no leaks anywhere in the system and fluid is clean and up to proper levels.
PAUL
I have no leaks anywhere in the system and fluid is clean and up to proper levels.
PAUL
Daniel PErkins
Member
- Joined
- Oct 5, 2013
- Messages
- 56
Paul--I am still leaning towards air in the system. Use the Phoenix reverse bleeder to get all the air out the system. What type of proprortioning valve is under the car? If you sucked all the old fluid out of the master--it may be possible you induced air into the system when the pump ran. Traditional bleeding with someone pumping the brakes did not seem to get all the air out of my system. You may have similar issues. Dp
standupjskiguy
Member
- Joined
- Mar 18, 2009
- Messages
- 237
So are you saying you now have more pedal travel after you installed the new accumulator?
That doesn't make any sense unless you had no power assist before and now because of the power assist,
the pedal will go down further because it has assist.
That doesn't make any sense unless you had no power assist before and now because of the power assist,
the pedal will go down further because it has assist.
- Joined
- May 26, 2001
- Messages
- 9,208
The accumulator ball and the "assist" side of the MC has nothing to do with the "braking" side or pedal travel?
If your pedal travel is down to the floor, you have air in the system, or more likely a bad or worn master cylinder which is allowing fluid to bypass.
As far as bleeding the brake side of the system, it is like any other of millions of cars w/o aPM, no special tool or pressure bleeder is required.
The cardinal rule in bleeding any brake system is to be SURE there is no air in the master cylinder. It must be bled first, then go to each wheel cylinder.
As far as the prop valve, it is just along for the ride when you are bleeding the brakes.
After 25+ years it is not reasonable to "assume" that just a ball replacement is the only wearable item that needs replaced in a PM, there are seals, o-rings, check valve and other parts that do not last forever.
In my opinion, if you want to retain the PM unit on your GN, get a fresh, rebuilt unit from Kirban and you will have a reliable unit that should give you lots of trouble-free miles w/o suddenly finding yourself, or your wife, with no braking assist.
If your pedal travel is down to the floor, you have air in the system, or more likely a bad or worn master cylinder which is allowing fluid to bypass.
As far as bleeding the brake side of the system, it is like any other of millions of cars w/o aPM, no special tool or pressure bleeder is required.
The cardinal rule in bleeding any brake system is to be SURE there is no air in the master cylinder. It must be bled first, then go to each wheel cylinder.
As far as the prop valve, it is just along for the ride when you are bleeding the brakes.
After 25+ years it is not reasonable to "assume" that just a ball replacement is the only wearable item that needs replaced in a PM, there are seals, o-rings, check valve and other parts that do not last forever.
In my opinion, if you want to retain the PM unit on your GN, get a fresh, rebuilt unit from Kirban and you will have a reliable unit that should give you lots of trouble-free miles w/o suddenly finding yourself, or your wife, with no braking assist.
X2 what Nick says. Power disasters are problematic and usually its wise to replace the whole unit when they start acting up. I did the accumulator replacement once only to have to replace the entire unit a few months later when it failed without warning and the car damn near killed me .After 2 more scary sudden system failures that soiled my shorts I pulled the pm and went vacuum. Only wish I did it before spending all that money on the 3 rebuilt powermasters.
Ok I hear what you are saying but I also have a few questions:
1. Can the proportioning valve introduce air if defective?
2. The car sat for six months, I then had more travel in the pedal than what it was before. What can cause air to get in from just sitting?
3. How can I tell if the master cyl is leaking by the seals causing the pedal to travel further and not building the hyd pressure?
I will bleed the system and see what happens, but I just don't understand why it is this way.
Thank you, paul
1. Can the proportioning valve introduce air if defective?
2. The car sat for six months, I then had more travel in the pedal than what it was before. What can cause air to get in from just sitting?
3. How can I tell if the master cyl is leaking by the seals causing the pedal to travel further and not building the hyd pressure?
I will bleed the system and see what happens, but I just don't understand why it is this way.
Thank you, paul
- Joined
- May 26, 2001
- Messages
- 9,208
1. With the thousands of brake jobs I have done over many years, only 2 prop valve were bad, one was in a car fire, the other someone messed with it?
2. One of my cars sits for a year or 2 and never had air in the system, and the 4k mile car I just finished had an original working PM.
3. Simple answer is if you bleed the system properly and still cannot get a good pedal, it can only be the internal seals are not doing their job.
2. One of my cars sits for a year or 2 and never had air in the system, and the 4k mile car I just finished had an original working PM.
3. Simple answer is if you bleed the system properly and still cannot get a good pedal, it can only be the internal seals are not doing their job.
standupjskiguy
Member
- Joined
- Mar 18, 2009
- Messages
- 237
Air can get into the system as it sits in cold climates as the seals shrink and stiffen from the cold.
Strange things happen when a car sits. My 68 Camaro has manual brakes and one half the brake reservoir
was empty over the winter. I found no fluid on the floor under the car. (Brake fluid evaporates.)
I filled it , bleed it and it's been fine.
Also moisture gets into and mixes with the brake fluid and can cause corrosion to form
inside causing a loss of a good seal.
But then some will probably say I'm wrong about this too even though I speak from personal experience.
Makes me not want to contribute at all to these forums.
Strange things happen when a car sits. My 68 Camaro has manual brakes and one half the brake reservoir
was empty over the winter. I found no fluid on the floor under the car. (Brake fluid evaporates.)
I filled it , bleed it and it's been fine.
Also moisture gets into and mixes with the brake fluid and can cause corrosion to form
inside causing a loss of a good seal.
But then some will probably say I'm wrong about this too even though I speak from personal experience.
Makes me not want to contribute at all to these forums.
Similar threads
