utahrock

My mechanic bleeds my clutch every time he bleeds the brakes, about 3 or 4 times last year. It's part of the tech inspection before a DE event. I just found out they have been topping the clutch off with brake fluid (in the front luggage compartment reservoir) and not the Pentosin power steering fluid that is specified for the Turbo.

It's an understandable mistake since the non-Turbos have a different clutch system and do indeed use brake fluid. The mechanic, who is the best guy I've ever used, feels terrible about it and obviously we'll flush the clutch system. But I'm curious if there will be any effect. There's not a lot in there; it still looks mostly like Pentosin. But do you think it has eroded the seals and one day the very fabric of the universe will be ripped asunder? Or is it probable that no damage has been done?

Basal Skull

hum that's too bad...
if you ask a porsche tech at a dealer I'm sure they'll say it's bad an want to flush/replace something. Not sure if brake fluid has lower density then pentosin. I would bet that the the reservoir is just a reservoir and the fluid hasn't made it into the system. I don't think I've ever had to add pentosin in the front reservoir in almost 10 years. Not sure how to tell for sure though, good luck

ca993twin

I can't answer your basic question, but I would have the mechanic suck the fluid out of the reservoir, top with up with pentosin, then flush the entire system. In the worst case, yes, the universe WILL be torn asunder.

Basal Skull

Btw, I've never bled the clutch, except when I changed the accumulator. Didn't know/not sure it's something that's required as part of tech?

utahrock

Yeah, I don't know how necessary it is. It was always stated to me that, since they were bleeding the brakes, the clutch might as well be bled, also. They say they sometimes get a few bubbles coming out if the car has been driven hard or tracked.

Droops83

Flush it out and you should be fine. Brake fluid is bad for paint, but is perfectly OK for any seals that would be in the clutch master cylinder circuit. The Pentosin that normally goes in there is the nasty stuff that you do not want to get on any other rubber hoses or seals besides ones that are specifically designed for it.

Mike J

Yeah, that makes sense. Make him flush it out at least a few times as well just to confirm it's all good.

I plan to flush this circuit out as often as I bleed the brakes - yearly. It does not take much time, and certainly not much fluid. I find the fluid does get dirty from the insides of the rubber hoses.

Cheers,

Mike

utahrock

Okay, they flushed it all out under pressure and I think it will be fine. As long as this was going on I bought some Pentosin myself and will suck up the old fluid from the power steering reservoir and replace it with new. I guess there's no maintenance spec on when to change it, but it's probably a good idea on a 16 year old car.

Thanks for the comments. This is such a great car!

Mike J

Yeah, it's good to replace the Pentosin in the engine compartment reservoir as well, but I am sure you know that as long as your slave is good, there is no transfer of fluids between the clutch circuit with the pedal, and the power steering pump circuit to the slave cylinder. Its when the slave starts to fail that excess fluid starts to build in the clutch pedal circuit, and the reservoir in the trunk fills, and then you have a mess on your hands.. LOL!

Droops83

The crazy thing is that Porsche has not completely fixed the issue . . . 996s still have the slave cylinders and accumulators routinely failing, and we just had an '08 997TT with only 15K miles on the clock in for service today with the clutch fluid reservoir overflowing!

Well, now that 80%+ of Turbos are being sold with PDKs, this may become a moot point!

rcg412

Amazing they still haven't fixed this issue. I thought was rectified in the 997... Is the forward reservoir still in the 997tt?