mousemat said:
Here's a question.

Last drive my P38 on Sunday. Left it parked on my driveway all week. Popped out to the drive Thursday to find a puddle of what looked like brake fluid based on where it was laying under the engine. I placed a metal tin under to catch the last few drips.

Opened up the bonnet to see that the brake fluid reservoir was full to the cap and looked like the fluid was seeping out of the cap.

Key in the ignition and waited for the pump to stop. Fluid in the reservoir now bang on the Max mark.

Left it overnight and popped the bonnet to see the fluid in the reservoir between the Max mark and the top of the reservoir. Looked at the tin and there were maybe three or four spots of fluid, I'm guessing these where from the residue dripping off the chassis.

No warning lights appeared at all. I've never put any fluid in. It's been hot here for the last few days and the P38 has been in direct sun ever since Sunday.

Checked it again this afternoon and again, level is between Max and the top of the reservoir. Only a few spots again, most likely what's coming off of the chassis.

Car drives fine and the brakes work with no issues. No loss of fluid when pumping the brakes.

Should I be worried? It's off to the garage Wednesday to be looked at
Click to expand...

I wonder if it is losing pressure somehow.
 
Grrrrrr said:
I wonder if it is losing pressure somehow.
Click to expand...
Not sure. I've driven it and it seems fine. I'll be driving tomorrow then taking it to the garage Tuesday night to be looked at. I'm not convinced it's leaking now. Just have to see what my mechanic says. I want him to install new bonnet cables anyway so he can certainly do that
 
Does it pump up to pressure normally and does the pump only come on every 3rd or 4th pedal press.
Does the pump ever energise without pressing the pedal? Ie ignition on or engine at idle?
 
Ok. Just popped out to test

Level half way between MAX and top of reservoir.

Ignition on - Pump runs for 22 seconds then stops

Level bang on the MAX line of the reservoir

Pump runs on every brake peddle press.
 
Probably a little too much fluid in there.

Pump running every brake pedal press usually means the accumulator needs replacing.
 
mousemat said:
Ok. Just popped out to test

Level half way between MAX and top of reservoir.

Ignition on - Pump runs for 22 seconds then stops

Level bang on the MAX line of the reservoir

Pump runs on every brake peddle press.
Click to expand...

If it runs every single press the accumulator, that black ball thing, is getting weak. My guess is the diaphragm inside is distorting from the pressure of the nitrogen gas inside and if left long enough it is pushing fluid out the top of the reservoir. I'd try replacing it. An oil filter wrench makes it easy.
 
I'll go one further and say every press means the accumulator is dead. You could have brake problems if you don't replace it.
The level is correct if it reads MAX when the pump stops, but check again once you've replaced the accumulator.
 
kermit_rr said:
I'll go one further and say every press means the accumulator is dead. You could have brake problems if you don't replace it.
The level is correct if it reads MAX when the pump stops, but check again once you've replaced the accumulator.
Click to expand...
As above, the accumulator is dead and if the membrane has ruptured t's possible that the accumulator is full of brake fluid which could run back into the system overfilling the reservoir
 
mousemat said:
Thanks for all the advice. I'll talk my mechanic when I drop it off and keep you updated
Click to expand...
When you replace the accumulator, you don't need to bleed the system, it should just start working as normal but you MUST make sure there is no pressure on the system.
I think RAVE says 30 presses of the pedal with ignition off, followed by a further 10 presses after a minute to ensure all pressure is gone.
 
Just an update on this.

My mechanic had a look and determined that there was no issue and all seemed fine.

Following on from the thread, I decided to purchase the accumulator and fit it myself. Looks easy enough....

However, it has arrived
IMG_20240608_142750.jpg
and maybe I'm missing something here. Am I to remove the top bolt in the picture? I'm guessing so as there seems no other way to fit it, but loath to just try and unbolt it if that's wrong.
 
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