Depressurize PowerMaster when not in-use

[GNONYX]

DO YOU THINK IT MATTER IF I DEPRESSURIZE POWERMASTER SYSTEM IF THE CAR IS NOT IN USE AFTER TWO WEEKS?
THE REASON WHY I'M ASKING, I JUST FINISHED TROUBLESHOOTING THE INTERMITTENT BRAKE LIGHT COMING ON AS I PRESS THE BRAKE.
AFTER DOING SOME READING RESEARCH, I HOOK UP THE KENT-MOORE J-35126 TURBO PRESSURE TEST GAUGE AND SAW THE ACCUMULATOR WAS LOSING PRESSURE, AND THE PUMP WAS CYCLING TOO SOON. I REPLACED THE ACCUMULATOR, RECHECKED, AND THE PRESSURE MAINTAIN 600psi FOR 30 MINUTES BEFORE I SHUT EVERYTHING DOWN. THANKS FOR ANY INPUT

 

[TurboDave]

Well, the accumulator already pre pressurized on the other side of the bladder, so de pressurizing the system won't affect/help that.

 

[GNONYX]

well, the accumulator already pre pressurized on the other side of the bladder, so de pressurizing the system won't affect/help that.

thanks dave for the extra info

 

[Slow91z]

I disagree Dave...Yes there's pressure on one side of the accumulator all the time, but there has to be more pressure on both sides when the system is pressurized not to mention the internal seals that sometimes go out in powermasters causing weird problems that are hard to diagnose.

If nothing else you aren't out anything by doing it.

 

[aminga]

Just to trow this out. Pressurized there is more or less equal pressure on both sides of the diagram. And the motor has to run more to bring it up from zero pressure to operating. Having said that It doesn't matter. I've gone through 2 in 25 years.

The BIGGEST thing you can do to help the life of your powermaster is to CHANGE the fluid regularly. It'll do far more than depressurizing the PM.

 

[TurboDave]

Leaving the system pressurized (leaving it alone) for extended periods of time isn't going to be detrimental to it. My 87 often sits for very very extended periods without activity, and both of them sit for months over the winter. This doesn't seem to be detrimental to their lifes span. I think my 86 is on it's 3rd accumulator in 25 years, and the 87 is on it's second in 24 years. Depressurizing the system just because the car has to sit for a couple weeks, especially if doing it enough times, can certainly be of no good.

 

[zeus87gn]

The BIGGEST thing you can do to help the life of your powermaster is to CHANGE the fluid regularly. It'll do far more than depressurizing the PM.

^^^^this^^^^^^

 

[aminga]

And it doesn't have to be too sophisticated. Depressurize the system, suck out the old fluid, wipe the resivoir down. Refill with fresh fluid.

 

[GNONYX]

I want to thank all for the inputs of my accumulator thread, and knowingly I replaced the brake fluid for some time.
My original question was not on replacing the brake fluid, but asking is it wise to Depressurize the accumulator ball since it does hold 600psi + pressure for a long time.
View attachment 147793
Assuming the accumulator ball is constructed in a Bladder formation, and NOT to spec. My first thread was base if the accumulator ball that has an internal pressurized nitrogen on one side of a diaphragm (gas chamber) and brake fluid is filled in the fluid chamber, and until the PM pressure switch set point is meet and then the valve close. Once the brake is apply the valve opens and the gas chamber forces the fluid chamber to the brake cylinder.
I know everyone has opinion's on how many years they replaced the accumulator ball, some of having to replaced 3 accumulator balls in 24 years and other replacement of 2 accumulator ball in 25 years, (not knowing the mileage).
I myself have just replaced my original black accumulator ball of 24 years with 92,400 mileage.
I was merely trying to make a point if the accumulator ball has this extremely high pressure on both sides of the chamber, and whether the car is stored two weeks, two month or two years, would that pressure may still be pressurized, and might weaken the nitrogen diaphragm (gas chamber), and or valve.
After I replaced the accumulator ball with the Kent-Moore J-35126 Pressure Test Gauge installed, the 600psi + pressure maintain for over 30 minutes. I really did wanted to see how long the brake fluid pressure would maintain the high pressure level, but I (shut down) Depressurize PowerMaster System since I didn't want to wait the final outcome.

 

[zeus87gn]

My original question was not on replacing the brake fluid, but asking is it wise to Depressurize the accumulator ball since it does hold 600psi + pressure for a long time.

I have recommended this in my bleeding procedure.
I have been practicing it for a few years now.
Over that time, I have not seen any negative effects of doing it.
One positive is that doing it will remove the pressure on the orings inside the pressurized portion of the cylinder and theoretically extend thier life.
The corresponding negative is that the sitting fluid will deteriorate the orings over time as the fluid gets older.
Hence my reply above.

After I replaced the accumulator ball with the Kent-Moore J-35126 Pressure Test Gauge installed, the 600psi + pressure maintain for over 30 minutes. I really did wanted to see how long the brake fluid pressure would maintain the high pressure level, but I (shut down) Depressurize PowerMaster System since I didn't want to wait the final outcome.

I would like to see this test gauge you have.
Would you be willing to post pictures of it?
If not, please PM me.
Your results prove your PM is healthy again.

 

[GNONYX]

I have recommended this in my bleeding procedure.
I have been practicing it for a few years now.
Over that time, I have not seen any negative effects of doing it.
One positive is that doing it will remove the pressure on the orings inside the pressurized portion of the cylinder and theoretically extend thier life.
The corresponding negative is that the sitting fluid will deteriorate the orings over time as the fluid gets older.
Hence my reply above.


I would like to see this test gauge you have.
Would you be willing to post pictures of it?
If not, please PM me.
Your results prove your PM is healthy again.

I have read any articles on our PM system including your thread (PowerMaster Accumulator - GN and T-Type Performance Enthusiasts (GNTTYPE) Forums) which was very informative, and lead to to do more research. I pick up the Kent-Moore J-35126 Pressure Test Gauge on EBay for $35.00 couple of months ago. Any say if you don't have this tool you can still troubleshoot the PM, and they're probably right. With this tool one can see if the pressure is holding steady or leaking.

 

[Rich Gio]

Wouldn't the pump have to run longer every time you start the car if you de pressurize the system EVERY time you shut it off? The pump/motor is way more delicate and expensive than the Acc Ball ... Just my opinion.

 

[GNONYX]

Wouldn't the pump have to run longer every time you start the car if you de pressurize the system EVERY time you shut it off? The pump/motor is way more delicate and expensive than the Acc Ball ... Just my opinion.

I didn't said to depressurize the PM system everytime you shut down. I'm referring to storing the car for more then two weeks of not in use. One of many reasons of doing this one can tell if the accumulator is leaking if it takes more than 15 seconds for the pump to stop running.