AAIIIC

iTrader: (19)

This weekend I took the car to Summit Point for a track event. Early on the first day of the event my slave cylinder died - at least, I'm pretty sure that's the problem, as the symptoms are the same as last time. Before I go throwing money at the problem I want to make sure I know what the cause is and I get it right this time. So, with that in mind, here's the full story...

~68k miles: Blew the engine at VIR. At the time it had a Fidanza twin disk setup with the stock slave cylinder. When I pulled the engine the Fidanza looked like it could use refurbishment, but they were no longer selling or servicing those clutches, so they gave me a deal on an ACT twin disk setup (T1S-G02). I installed the clutch on the engine myself, keeping the stock slave (which already had a slave spacer on it due to the previous Fidanza setup). I did not take any measurements of the clutch or slave, I just installed it as it came out of the box.

Winter '13/14: It was getting progressively harder to get the trans into reverse, particularly when it was cold. I started leaving the trans in R (rather than 1st like I normally do) so that I could just start the car and it would already be in the gear I needed to back out of my driveway or a parking spot. I changed the trans fluid with no improvement.

~77k miles: Slave cylinder died about 60mi from home as I was nearing the end of a ~450mi trip. I stopped at a stoplight and had trouble getting away from the light - the clutch was grabbing instantly off the floor and I stalled it a couple of times. A few miles down the road I caught another stoplight, couldn't get it into gear even with the pedal on the floor, and then the pedal went to the floor and stayed there. Rolled into a parking lot, tried bleeding the clutch, but fluid was just coming out the bottom of the bellhousing. Got towed home, and ended up having a shop install an LS7 slave. AFAIK they did not do any shimming of the slave - I'll find that out Monday AM, as I'm towing the car there to be fixed again.

I was hoping the new slave would fix the reverse engagement difficulties, but no such luck.

Past couple/few months: Once spring rolled around getting into reverse wasn't as big an issue. However, over the past few months I've routinely had issues getting into 1st from a stop. Sometimes it goes in like butter, other times it would get like 1/2 way and stop. Easing up on the clutch pedal would allow it to slot into 1st. Sometimes it would feel as though the car was creeping forward slightly as I put the lever into 1st. Strangely, though, it would only do it for a split second, and only as I was moving the lever - once the shifter was actually in 1st, it was fine.

~90k miles: LS7 slave died at Summit Point. Saturday morning as I was prepping the car I decided to bleed the clutch, as I hadn't done it in a while and I had been having the shifting issues described above. Bled the clutch (I've got a remote bleeder), then went out for just a few laps in the first session to bed in some new pads, no issues - didn't seem any better or worse than before.

Went out for the second session and about 10 laps in the clutch pedal started to get weird - it would come part way up, then "jump" back to the top of its stroke. (Of course this happened 1 corner after the front/pit straight... ) Obviously that ain't right, so I immediately backed off and started to limp back around to the pits. I pretty much kept it in 4th for the rest of the lap. Got off track and went for a cool-down drive through the paddock and approach roads. Started to get a pretty loud whirring/whining (bad bearing type noise?), which would go away if I depressed the clutch pedal part way. Parked it, found the clutch MC low, added fluid, cycled the pedal and it went to the floor and stayed there. Fluid out the bellhousing again, weekend over.

General comments:
- I know I've read about other folks having issues, but I've never had a problem with high RPM shifts on the track or the street. That includes with everything stock, with the Fidanza/stock slave setup, with the ACT/stock slave setup, and with the ACT/LS7 slave setup.
- As I said above, I didn't do any sort of shimming when I installed the ACT clutch. It wasn't until the past 36hr or so that I even started to learn that such shimming might be necessary. I think that the clutch only came with these generic instructions, so I don't think I did any of the stuff spelled out in the kit specific instructions when I originally installed it.
- The stock slave worked just fine for 68k miles, first with the stock clutch & flywheel, then with the Fidanza clutch & flywheel. The fact that the stock slave died ~9k miles after I installed the ACT setup, and then the replacement LS7 slave only lasted ~13k miles, leaves me to think that there's something wrong with the way the ACT setup is working with the slave.

So, is this just tough luck on my part? Is this a sign that the slave needs to be shimmed? Is this a sign that I need philistine's new master cylinder setup?

Keeping in mind that the clutch worked (at least for a little while) after I bled it, is there something that I could've done while bleeding it that would've caused a failure, or is it just a coincidence that it finally **** the bed shortly after that?

gtistile

Dont bother w/ another slave until you upgrade the master cyl with it. I lost a 4,000 mile slave with the LS9 clutch (which has the same throw length as the CTS-V slave, so they are matched up w/ out shimming) just before I did the Tick master in my car. I think the hydrolics (master cyl) just not having enough *** behind them to really do their job moving a heavier pressure plate puts a lot of unnessary strain on the slave. Just my guess since now after upgrading the master, ive driven the car MUCH harder and havent had a single problem

philistine

iTrader: (2)

This is one of those "experience" base feedback threads. I can only share my experience. After installing my Katech LS9x twin clutch, things were good for the first tank of gas of just street driving. Then I noticed my shifter became more and more notchy and a little crunchy. I bled the clutch again and I had the remote bleeder. Things got better but then the notchiness and crunch came back. I purchased the Motive Power Bleeder - again things improved then went back to the notchiness and crunch.

At that point I called Jason at Katech and groomed the forums for any advice. Jason gave me a list to confirm and then everything pointed to the hydraulics. So I dropped the transmission and installed a new factory slave - bled some more. Again, things improved but notchiness and crunch came back.

I decided to just power through it since I did everything I could. Then I started getting disengagement issues, blocked gears and an impossible reverse. Quick solution was to just double pump my soft pedal.

I was ready to purchase a new factory MC when a thread popped up about adapting the Tick to the V1 - it's all history now. It solved my clutch hydraulic issues. There is less than a handful of experience with an aftermarket clutch MC and a wealth of experience dealing with an assortment of clutches, slaves, shims etc.

In theory, all of the aftermarket options are suppose to work but empirical feedback says otherwise. You have done a few combinations already and I would apply process of elimination. Provided a proper clutch install, I point my finger at the hydraulics. Why? because that is where my path led me.

It doesn't directly answer your question but figured I'd give you my story - in the end it was the master cylinder that made all the difference.

Reference post: http://www.cadillacforums.com/forums...ch-master.html

Onefast V

iTrader: (3)

I had the same problem with my ls9. I replaced the slave and the master and still had crunchiness and a lot of difficulty shifting. I ended up moving to an ls7 with no issues but never could figure out the ls9 issue.

AAIIIC

iTrader: (19)

So, not only is the slave dead, but a chunk of the bellhousing is cracked off, too. I'll post up the pics when I get home from work; just stopped by the shop over lunch-time so I could see it for myself. Looks like the crack originated around the hole in the bellhousing where the slave bleeder comes out, but it's not from any interference with the remote bleeder. Very strange. The only things I can think of are either (1) the crack originated from a pre-existing casting flaw, or (2) some sort of shock load from when I blew the engine a couple years back caused the initial crack.

Fuzzy_Wuzzy

iTrader: (8)

Are you sure that was not done when the bleeder was installed with the LS7 slave? they can point slightly off of the stock hole.

That would be a strange location for a natural crack to happen

I know in the jeep world they often recommend replacing the master and slave at the same time when one goes out as often the master starts to go and can take out the slave cylinder. not sure if it carries over here, but probably a good practice.

AAIIIC

iTrader: (19)

Here's the failed slave, which basically looks exactly like the last failed slave:


And here's the broken bellhousing (top is to the right in the first two pics):






In that last pic you can see that the remote bleeder isn't close to rubbing in that area.

philistine

iTrader: (2)

What a smooth break on that bellhousing. Looks like it originated close to the bleed port then followed a grain boundary path.

Fweasel

iTrader: (6)

2nd. Not my field of expertise, but I've seen enough examples and it looks exactly like a natural path from the bleeder out.

69stangscj

iTrader: (3)

Just thinking about this, where do you think the stock master cylinder is failing, and not letting the slave reach it’s stroke? It’s not the fluid it’s self unless contaminated, the lines flexing, the master housing flexing, seals letting fluid by? I’m just trying to understand why the stock master is causing problems?

Sssnake

IME the stocker was failing to handle the clamping pressure. Until I swapped to the Tick nothing would cause my RXT to fully disengage after about 100 miles. You could bleed it and make it better but nothing actually fixed it. The things is you really don't know there is a problem until you get something like the Tick in there. My V had always shifted with a little resistance. Now it is easy peasy even with a very short shifter. I attribute that to the fact that the clutch is fully disengaging.

odthetruth

iTrader: (4)

I have this issue on stock clutch. With letting off the clutch making getting into gear easier on both R and 1st, with going into 1st showing a very very slight 'surge' forward.

I kicked the clutch all the way in, with car in 1st, and rev'd to 6k, and the car moved forward. Dragging pressure plate is what I assume. Have you tried this at all?

philistine

iTrader: (2)

The McLeod has as much or more grip than my Katech LS9x twin clutch and I was having the same issues with the factory MC. Went down the same path everyone has...bleed, swap slaves, try new clutch fluid...bang head against wall etc.

After I installed my "philistine master cylinder", hydraulic issues went away and I have full disengagement. It does make shifting much easier and smoother and got rid of the awful "crunch" and notchiness I was having.

When you experience a problem like that it can make anyone desperate...angels were singing after I did the install on my clutch MC.