So my 190D with the 5 speed brake fluid keeps dropping down and the first thing that happens is clutch becomes inoperative and i need to bleed the slave cylinder. I couldn't see any brake fluid leaking anywhere.

So the other day i topped off the brake fluid while i was jump starting my truck with the 190D . I let the 190D idle for 15 min . Then stopped it started again and let it run for 20 min or 30 or more. Anyway i then go to move the 190D and the clutch pedal goes to the floor. Damn! I check the reservoir and its low again. So it lost fluid just sitting there idling.

So i didn't drive the car, just let it idle and it lost break fluid. The puddle seems to be under the booster area but i didn't see any leaks under the hood, around the reservoir or rubber hose connection to the clutch system. . Could the booster be sucking brake fluid in from the vacuum in it?

Maybe the rubber hoes going to the clutch master got damaged or has a hole. That would explain why its not leaking under the hood. I don't see any leaks in the car either.

Also, could i rig up a separate reservoir in the meantime so i don't have to keep bleeding my clutch and isolate the problem.

Thanks

__________________
What Would Rudolph Do?
1975 300D, 1975 240D, 1985 300SD, 1997 300D, 2005 E320 , 2006 Toyota Prius

my guess is the brake booster is sucking the fluid out of a leaky master cylinder when it builds vacuum. i bet your booster us full of fluid and could be damaged. i imagine it fills up enough it will get drawn into the vacuum pump and dumped into the crankcase of your engine.

__________________
83 300CD- sanden, dual p/f condensers, 160a alternator, ect
91 300TD- 722.6, #22 head, 3.5L IP, w140 manifolds, ect

If you lost the clutch then I doubt the leak is in the brake system/booster circuit. The clutch is fed by the brake reservoir with a hose on the right side of the reservoir ( I think ). It must be losing fluid in the master or slave cylinder in the clutch circuit. Have you checked for leak at the master cylinder behind the carpet? Or use a flashlight to check the slave cylinder next to the tranny?

__________________
Not MBZ nor A/C trained professional but a die-hard DIY and green engineer. Use the info at your own peril. Picked up 2 Infractions because of disagreements. NOW reversed.

W124 Keyless remote, PM for details. http://www.peachparts.com/shopforum/mercedes-used-parts-sale-wanted/334620-fs-w124-chasis-keyless-remote-%2450-shipped.html

1 X 2006 CDI
1 x 87 300SDL
1 x 87 300D
1 x 87 300TDT wagon
1 x 83 300D
1 x 84 190D ( 5 sp ) - All R134 converted + keyless entry.

Thanks. I did look there. Didn't see any. I'll check again closer. But why would it leak just sitting there? It's done this several times. First I thought I just didn't top up brake fluid enough. Second I thought hose may have been not right enough at the reservoir. And now it's done it again.

It dropped really fast idling 30 min which is why I thought the vacuum action might be a clue.

__________________
What Would Rudolph Do?
1975 300D, 1975 240D, 1985 300SD, 1997 300D, 2005 E320 , 2006 Toyota Prius