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Transmission/slave drip on passenger side -question?
Basics:
pentosin drip from passenger side of manual trans, in front of driveshaft
bbi slave, so shouldn't fail, no accumulator to fail
bbi slave feels dry reaching from passenger and driver side
power steering pump doesn't look like the source -and it's 4k miles old
clutch just recently felt funny, reservoir was empty, explains source, filled, and new feels right
Where's the leak?
Details
Drip still there. Seemed like more. Was moving it to put it on stands and clutch had free travel the first 1/4 of the way down. Front clutch reservoir was empty. Lots of reading about slaves going bad, accumulator going bad, or both, puddles under driver, etc. Filled the reservoir, pumped pedal and it feels right now. Haven't driven it, but feels right. Power steering pump was full. Pump was a little dirty, not dirty enough to be source of leak. Even if it was, the drip would be though the engine bay. Records show pump was new 4k miles ago. Cleaned up pump area and front reservoir area too. Car has what looks like the bbi slave. It's black, as much as it's visible, it looks like it and feeling it blind, it feels like the pictures look. Slave was on the car when I bought it in Jan2018 and I don't have records. Feeling above the drip in the bottom photo, everything was dry. Driver side where the three lines come out of slave was also dry. I'm stumped where the pentosin is dripping from. To drip on the passenger side, maybe from where the slave attaches to the trans, but it's not wet. If the slave is leaking at one of the hose connections, it would drip on the driver's side. Last idea, the front-most hose, where does that go? Car is lowered and I don't remember! Does it go over the trans, as in the photo from above? Could that connection be bad? I'd really rather not drop the motor to look. I'm stumped.
bbi slave from side
bbi slave from top
.
From the passenger side, looking up, passenger rear axle on left, plastic-wrapped cables go to starter, center is where the drip forms.
Your BBi slave has failed and is leaking secondary to installer error.
If your slave reservoir is empty, the slave is leaking. Had EXACTLY the same symptoms. Now that you have fluid back in your reservoir, go check and see if it's turning black. It should be clear and have zero debris in it.
100% installer error. Your system was never converted from pentosin to DOT4 or incompletely flushed. The pentosin breaks down the seals on the piston in the BBi unit. My "Porsche master mechanic" never converted the fluid over after the install on my car. I rebuilt the slave and did the conversion myself. Fine ever since. It leaks out of the front of the unit where the silver pin comes out. The good news is the rebuild kit is around $250 shipped, and the BBi unit is much easier to remove and reinstall than the bulky factory one is. It really wasn't that bad. You'll need to make sure you flush the system well to get all the tarry bits of black crap and degraded seal out. I let mine run clear for nearly a liter with a vacuum bleeder hooked directly up to the bleeder valve on the slave.
I wrote on the cap for the reservoir as well as flipped the "pentosin only" ring upside down, and wrote on that. You can also see the green hose that I ran to replace the failing/seeping factory rubber line I reference below:
Are you tuned? People who have tunes making decent power, even with the Sachs 2.5 with this issue will begin to notice random, and short amount of clutch slip at peak torque. This was the first thing that I noticed, and I've seen a couple others post about it as well. The leak drips fluid down onto the friction disc and decreases the coefficient of friction substantially. Once I repaired mine, 3-400 miles of street driving and the affected friction material burned off/pentosin vaporized and everything was back to normal.
One other thing: After I converted to DOT4, the rubber line that runs from the bottom of the reservoir to the plastic slave cylinder nipple at the firewall swelled and began to seep, so I replaced that with some hydraulic line as well. Can't use fuel line, it isn't rated for DOT4. Expect this to happen to your car and plan accordingly as well. Very easy fix.
That sucks. I sure hope you're wrong! Thank you. This is great information. Sounds like my issue. Since I didn't know bbi is dot4 only and the pentosin reservoir label is still there, I filled the reservoir with pentosin. No way to tell what was there before, not sure if I even could. I went to the bbi site and the dot4 warning is pretty clear. Is the turning of the pentosin dark the indicator that the seals are bad? Is it actually the seal material that is darkening the pentosin? If it wasn't damaged before, I just did damage by adding the pentosin. I'll call bbi on Monday and see what can be done. My clutch reservoir:
Even if that triangle with the drop in the center means dot4, the pentosin label is still there.
I don't have a tune. I haven't noticed any slip though. I was the clutch was 'improved', but I never got the records.
Thanks again. I'll let you know what I learn.
Unfortunately, that is your problem 100%. Yes, the black is from the seal dissolving in the pentosin. Like I said, at least you now know the issue and can get it sorted. It shouldn’t be terribly expensive and it’ll be all sorted once you’re done. Any pentosin contamination will lead to this, but I suspect your system was never converted at all, just like mine.
I'm thinking you're correct. It's definitely a bbi slave and the pentosin label is definitely on the clutch reservoir. Difficult for a 'mechanic' or anyone else to put dot4 in there and not remove the label. I don't see anyway that it could have had dot4 in there. I'd love to be able to blame someone. The dealership told me it probably had the gt2 slave because it was so hard to push and the salesman said he thought the guy that took in the trade had mentioned it too. Nothing about it being something else. I don't think they did it, but they passed it along without looking. How does someone install this without reading the instructions? I knew some things to look for when I was shopping, but hadn't heard about this one. It took 5 months for it to leak on me. One data point though. I sucked the pentosin out of the reservoir and refilled it. The new fluid was also very dark without any pumping of the clutch. I don't doubt you're correct with the discoloration coming from the slave itself. I don't have any chunks showing yet. Thanks again for your help. Calling bbi in the morning. Hope that rebuild is still $250. Not looking forward to doing this on the garage floor.
You’re welcome. Hard to be the bearer of bad news, but with these cars this issue is fairly minor in the scheme of things.
Don’t have to have debris, but when you pull and clean your slave reservoir you’ll notice junk in the bottom. I don’t recommend doing this on the floor. You have to lower the motor down a bit (very easy, two bolts) to get enough room to work up in there and that would be terrible to do on your back. Find a lift, or get cozy with your new independent Porsche mechanic.
It is also a great time to give the rest of the car a once over while you’re underneath and have the panels off. I found a recently torn CV boot and fixed that at the same time.
You wouldn’t have read about this issue. It is a new failure as it is a new part and only now are the cars that weren’t properly converted showing signs of seal failure. My car made it a year and a half before I began noticing issues (installed March of 16). I meant to write up a post on this issue, but your thread is as good of a place as any. BBi is aware and the rebuild kit is very reasonably priced considering the cost of the unit new.
I am very happy with the BBi unit. It is easier to install than the GT2 slave, and it provides similar feel. I hated the stock setup so as soon as it began to fail, I tossed it. The clutch effort is substantially higher, but you get used to it quickly and having a predictable/unchanging clutch engagement spot in the pedal travel is worth any increase in pressure. You can add a GT3 helper spring to drop the clutch effort back down, but I've gotten used to it with the factory helper spring in place. I imagine if you live somewhere where you might get stuck in traffic fairly often, the GT3 spring would be of greater value.
That really is too bad...I bought both a BBi slave (from the marketplace) and the EVOMS GT2 conversion kit - each one of them comes with a new replacement DOT4 cap for the fluid reservoir. Sounds like the PO or installer messed up.
Look at the bright side, at least you don't have to deal with the vague factory hydraulic system (which itself will fail periodically from the nasty pentosin). I'm loving the feel of my GT2 EVOMS kit, which came with the GT3 spring - the required pedal effort isn't bad at all IMO - note I do not DD this car.
Are you happy with the setup? Would you d it again or would you go GT2 setup or stay stock?
I have the gt2 setup with helper spring and a twin disc clutch set up. It feels 100000% better than the stock set up. You can actually feel when the clutch with engage.
I tapped my trans and run the gt2 slave on the right side where it would have come from the factory.
Also replace my clutch master just because of the mileage on my car but its not needed
I have all the part numbers you need for it let me know if you want them
07-21-2018, 04:32 PM
Transmission/slave drip on passenger side -question?
