ACEparts_com

Would turbo owners care to do the following in order to tell me if my brake accumulator is shot or not?

Turn ignition to first position

Wait for brake booster to stop running

Pump the pedal and count how many pumps you do before the booster pump restarts.


I only get THREE pumps. I'm sure it used to accumulate more?!

Thanks

Knight

I just recently did this test after a tech told me my accumulator was on its way out.

If your only getting 3 then yes it is, I got about 20 pumps before the pedal gets really stiff again.

Johnny_law

Knight, the OP is testing the Brake accumulor not the Clutch Accumulator. The latter is what U think you tested getting 20 pumps before getting stiff. (OMG that just sounds wrong).

What the OP is talking about is the brake accumulator which is in the frunk. I've never tested mine as it is difficult to hear when the motor comes on. Once in awhile if the car hasn't been driven I need to wait a minute for the system to pressurize.

Johnny

PiB993

When the clutch accumulator fails the pentosin overflows in the frunk I thought??? I had mine replaced.

Knight

Yep my test was referring to the brake accumulator, one of our local shops said to test it by pumping the brake pedal.

Johnny_law

Thanks for correcting me Knight. I'll have to experiment with the brake pedal but it's always a bit stiff. I guess it will really stiffen up when there is no accumulator pressure help.

As far as the clutch, my understanding is that failure in the system that backs pentosin back up the reservoir in the frunk is caused by failure of the slave. A leak from the high pressure (power steering pump) to the low pressure (Clutch mechanism) not necessarily in the clutch accumulator. Once again testing the clutch accumulator should result in 20+ presses of the clutch with the engine off until it stiffens up. This could pass fine but still have an issue with pressure leaking to the low pressure side.

Back to regular schedule programming.

Johnny

WingChun

Three pumps is not good, mine was like that a while back, now it so bad if I just leave it with ignition in that position the pump kicks in every few minutes!

I have a new one to swap it out but looks like a PIA job.

ACEparts_com

Well, that's my thought. Three pump of the BRAKE pedal and the pump cuts back in for a few seconds. How many do you get between electric pump runs?

WingChun

Can't try it now because I have front calipers off for refurb but I can recall only a few pumps of the pedal before electric pump started to rebuild pressure.
Luckily I managed to buy an unused brake accumulator off ebay for £50, not sure on new cost though, maybe 2 or 3 times this.

So I am now faced with replace brake accumulator and also clutch slave as this is now leaking pentosin all over the transmission.....fun time ahead for me.

911PERVY

Well I have just tried mine, 3 pumps then motor cuts in for a few seconds...............more money to spend? FFS

ACEparts_com

Perhaps a few others will chime in with their results....

PiB993

I believe I only got about 2-3 pumps too. It's basically the only sound you can hear and it comes from the dash. Pump turns on, turns off, car is silent, pump brake 2-3 times, and sound comes back on - cycle continues.

I was detailing my car and had no run the engine at all while doing this test. I'll drive it later tonight. Anything else to look out for regarding this?

O/T - Do the hydraulic clutch and the power steering run on the same circuit?

DiegoR

I never did this test (brake) however the clutch once I turn the engine off even leaving the IGN ON, the clutch pedal get stiff again quickly if pressed in this situation. As I understand the clutch system is assisted by the pump steering hydraulic that power up the acuumulator of the clutch hydraulic, etc THAT is driven by the engine when (steering pump) is operating and not a electric pump like does the brake vacuum ? If I'm correct, how does work the 3 or more pumps of the clutch pedal test?

PiB993

I think that it's true the steering pump powers the clutch too but only with engine on.

I guess my brake accumulator is on it's way out after further testing and driving. I think I can hear it running when I'm driving too. Any further info on replacing the brake accumulator would be welcome - parts to replace, cost of parts, hours to replace, cost with labor at a shop, anything else to do while it's getting fixed.

I'll be doing a search now.

PiB993

Bump - Any further info on replacement and repair?

My car must have been this way for awhile I guess - is it dangerous to drive like this? Brake warning light coming on after starting for a few seconds was normal I thought but maybe a sign too of brake accumulator failure.