I am trying to remove and replace my brake accumulator, but it will not budge. Any advice? Used a ratchet with Allen socket and vice grips holding the base. I’ve read to remove the whole assembly, any tutorials for that?

My brake light and anti-lock illuminates every time I press the brake pedal but only in PARK. When driving it doesn’t light up. In PARK every time I depress brake pedal you can hear the electric motor run for approx 1-2 seconds.
When initially putting the key to position two the electric pump runs for approx 1-3 seconds.
When driving braking seems fine maybe a little soft but otherwise fine.
Is this any cause for concern or should I just leave well enough alone?? Thanks

 

If it doesn't light up after cruising along for a while and then when you press the brake and nothing illuminates, it's probably just fine.

Soft pedal is normal, hard pedal is bad (no power assist!)

Larry

 

I use GIANT channel lock pliers or a band type oil filter wrench along with the socket head wrench.

bob

 

Thanks for the help guys! Got it replaced, here are the results: used GM part# 25676065 it was $104 shipped to the house. Screwed right in, on initial key turn the electric motor filled the ball for approx 30-60 seconds. No more lights at all! Brakes are much better. I believe my rear brakes were not engaging with the old accumulator ball.

Here are some pictures of the set-up I used. 1 and 1/8in wrench holding the base of the assembly and a big long breaker bar and Allen socket. Broke loose on the first try and was able to unscrew by hand after. I did give it a small shot of liquid wrench the night before not sure if that helped as well.



GM part number 25676065 on the left. I’m assuming original one one the right, that’s the one that came off the car

1 and 1/8inch wrench holding the assembly


Didn’t take a picture of the old accumulator ball but here is the GM one installed

 

What did you do with the accumulator to take the pressure out of it prior to unscrewing? This worked on the 91 sovereign ok? Asking because mine is a 91 sovereign vin 658822

 

KEY OFF, pump the pedal till you leg muscles get tired.
Remove accumulator,

 

I just changed mine. Was expecting a project of it, what with all the things to disconnect if I was going to have to pull the whole assembly & put it in the vise. Instead, I shimmed the assembly tight in place with wood bits so it was locked in position. One good grunt & she's loose! Directions with replacement ball referred to adding new fluid to the accumulator reservoir, I assumed that's the ball itself. What little went in, dripped back out upon installation. Road test! I have brakes like I've never had before in the 9 years or so of owning "Bigkitty". Just a slight left pull sometimes, & the brake light still lights upon activation of pedal. Next up is whole system bleed, as the fluid is ???years old & a bit dark. So a successful half-hour under the bonnet, we're both happy.

 

Hi catmanboo,

Once potential cause of the BRAKE light coming on when you press the pedal is a brake pad wear sensor is worn and grounding against the rotor when you activate the brakes.

Cheers,

Don

 

Reviving an old post here for my 1992 XJ40. I also changed my accumulator ball with the GM part as Stran0020 did (Thanks for the info, saved a bunch of $) and the brake light no longer comes on. My only problem is on initial start up. Every time I start the car, the brake light comes on and then after 30 seconds or so goes out and doesn't come back on again unless I park for an extended period of time.

Any ideas?

 

The system is operating NORMALLY. What is your concern?

 

Hey Motorcar, my concern is that despite its normal operation, the dash brake light still comes on when first turned on when it shouldnt be. The brake pedal also doesnt feel solid when this light is on so if i had to move the car in a hurry, it could pose an issue.

 

That is normal. The systems is doing a self check and the light stays on longer than the others.

 

OK thanks

 

The pump requires TIME to build up pressure to operate the system.

 

Whats curious is that this never happened before until i replaced the accumulator. The accumulator i replaced it with was larger than the original one that was in the car so I am wondering if perhaps that is the cause. Has anyone else had this be the case?

 

When the accumulator sphere is full of brake fluid, there is no nitrogen charge on the diaphragm to 'pressure-up'.(build up pressure for brake operation)
The nitrogen and diaphragm requires time to charge. (accumulate pressure)
A sphere full of brake fluid cannot be compressed. (cannot compress hydraulic fluid without diaphragm and nitrogen)

The pump will only run for a second with no nitrogen left in the sphere. That is why you never noticed the longer time to pressurize the system.