tj90

I have a 95.

JimGinKC

can i add to the confusion, or its probably just my confusion. I got Adrian's 993 book, and since I just got some fresh brake fluid to bleed brakes, I thought great, now I have a manual. Well, in the book it refers to this hydraulic pressure accumulator - i have a 95, and according to my window sticker, it has LSD with ABD. do I have to follow this procedure? The book does mention clamping off the vent hose - can bleeding the brakes really be this complicated??

zwoobah

I would bet that the wax is not necessarily from the fluid, but from the plastic of the brake fluid reservoir. I've seen this happen a few times when the fluid goes an exceptionally long time without being changed (once was on an older Audi that had sat in storage for about 6 years). If that's the case, it will not be reabsorbed by the new fluid. I would follow VB's abvice and completely remove each bleeder screw, to make sure there's not any "clots" in there. Even after you do that, changing the brake fluid again in 6 months or so is a very good idea, as there is probably wax in the lines as well.

planeguy67

Now you tell me. Where were you when I bought the darn thing???

planeguy67

That is correct. The Porsche Service Manual says, "The overflow hose/venting hose has been omitted as from October 1995; see Technical Information, Group 4, No. 16/95."

The hose is still there on my '96 C2, so I clamped it off just to be safe (wiping up brake fluid is such a drag).

planeguy67

It is very confusing and had me baffled for a while as well. I'm not sure where I read it (maybe it was here on rennlist!), but I believe C2's use a vacuum brake booster and may be bled/flushed like a "normal" car while Turbos and C4's use a hydraulic boost pump with accumulator that requires a few extra steps.

Hopefully someone else can confirm this so you don't break your car listening to me.

faster

planeguy67, do a search, i think you will find this issue a couple times. it is the brake fluid itself breaking down. you will also notice many people here will advise you to change the fluid on a regular basis and use a good quality fluid.

good luck!

tsjoel

Planeguy,
My first brake bleed was similar to yours. I had to resort to a carefull brake pumping. The fluid never really got moving like I really expected but I did get all new fluid in the system. The good news... the next brake bleed (about 9 months later) went great. No pumping needed and the fluid flowed nicely. Good luck.

planeguy67

Thanks Joel. I plan on flushing the brake system again later this year after I give the new fluid some time to absord some of the impurities in the lines and carry them out.