LS7 clutch users
11-04-2006, 04:18 PM
#1
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LS7 clutch users I just installed the LS7 clutch/LS2 flywheel combo today. After the install, I noticed that my clutch engagement point is much lower to the floor now, I'm talking like 1/4" from the floor, while it used to be more like an inch or slightly more with the stock clutch. Has anybody else experienced this? LS7 clutch disk and pressure plate, LS2 flywheel and a new slave cylinder is all that was replaced. System fully bled. I can't figure it out and I don't like the engagement point being that low.
11-04-2006, 04:44 PM
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Are you sure it's bled????? It sounds like it has a tiny air bubble.....
I had a similar problem, and no one to help bleed, so this is how I did it.
Pump out (depress pedal) If pedal has pressure, cut a 2x4 to hold it to the floor...
Open valve for 1-1.5 seconds.
Close valve
Repeat 3 times.
Refill reservoir
Repeat whole process 2-5 times, depending on your dedication to the cause.
If this doesn't work, then there could be a problem with the clutch piston attached to the clutch pedal..... Or there might be a conflict with the clearance between the throwout bearing and the clutch fingers.
One question.
What is your pedal free play? Check the service manual for the specifications, but if I remember correctly it is about 3/4 of an inch. (or at least that is what mine is at)
Don't rule out defective slave cylinder if nothing else. I bought a Bendix (yeah, I know) and it was OOC in about 48 hours. Just a bad unit.
I had a similar problem, and no one to help bleed, so this is how I did it.
Pump out (depress pedal) If pedal has pressure, cut a 2x4 to hold it to the floor...
Open valve for 1-1.5 seconds.
Close valve
Repeat 3 times.
Refill reservoir
Repeat whole process 2-5 times, depending on your dedication to the cause.
If this doesn't work, then there could be a problem with the clutch piston attached to the clutch pedal..... Or there might be a conflict with the clearance between the throwout bearing and the clutch fingers.
One question.
What is your pedal free play? Check the service manual for the specifications, but if I remember correctly it is about 3/4 of an inch. (or at least that is what mine is at)
Don't rule out defective slave cylinder if nothing else. I bought a Bendix (yeah, I know) and it was OOC in about 48 hours. Just a bad unit.
11-04-2006, 05:00 PM
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they all start out low... try rebleeding it one last time just to make sure and go with it.. over the last 800 miles mines gone from engauging right off the floor to pretty close to normal now.
11-04-2006, 05:57 PM
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Free play seems to be more than it used to... I definately don't like the low engagement point. I'm starting to think there is still air in the system. I talked to a friend that has a transmission shop and he said it's either air still in there or the slave cylinder needs a shim. The slave cylinder is a brand new OEM part, I'd hope it's not bad...
Meeting a bunch of people out tonight for a meet, the transmission friend will be there. Going to let him drive it, see what he thinks. If he thinks it's air still in the system, going to try to convince him to MAYBE take it to his shop (just down the road from the meet) and try a quick re-bleed...
Meeting a bunch of people out tonight for a meet, the transmission friend will be there. Going to let him drive it, see what he thinks. If he thinks it's air still in the system, going to try to convince him to MAYBE take it to his shop (just down the road from the meet) and try a quick re-bleed...
11-04-2006, 06:08 PM
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with a friend a bleed will take 5 minutes. Maybe try pumping the pedal about 50 times while sitting there.......... I find that helped before.... But bleeding is 100% sure. ..
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11-05-2006, 02:17 AM
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Has my friend drive the car tonight. He said he could tell there's no air in the system, so he's going to give me a shim for the slave cylinder that he's got at his shop. Will probably hold off on putting it in to see if the engagement comes up on it's own. I'll give it a week or so before I decide to pull the transmission back off...
Besides the whole engagement thing, everything else about this clutch I'm diggin'... Feels much better than the stocker, car seems to ride better, even seems better balanced for some reason...
Besides the whole engagement thing, everything else about this clutch I'm diggin'... Feels much better than the stocker, car seems to ride better, even seems better balanced for some reason...
11-05-2006, 06:33 AM
#9
Ask your installer how he installed the slave and master, more importantly how he bleed the system. When I first installed mine, it was right off the floor, after a couple weekend drives, it self adjusted from (1) right off the floor, (2) to just right , (3) to a little high for me. I had an Mcleods adjustable master cylinder installed and (4) readjusted it a hair lower. A couple hundred miles after that, the clutch pedal started to stick to the floor. I changed the fluid in the reserve about 5 times. After about a total of 1500-2000 miles, I had 3:90 gears installed, had the LS7 clutch removed with the McLeods, and installed a Textralia clutch with a stock pedal.
Nothing against the LS7 clutch because I liked it while it was working, but it was fairly cheap to replace the clutch when everything was down while replacing the gears. Maybe bleeding it again could have worked, but for one it's a bitch to reach the bleeder with the torque tube in a C5, and I didnt want to button it all back together to find out bleeding wasnt the problem. During the 1500-2000 miles, I has no track runs, no racing, just normal week break in driving. $1500.00 lesson.
Just a little food for though.
Nothing against the LS7 clutch because I liked it while it was working, but it was fairly cheap to replace the clutch when everything was down while replacing the gears. Maybe bleeding it again could have worked, but for one it's a bitch to reach the bleeder with the torque tube in a C5, and I didnt want to button it all back together to find out bleeding wasnt the problem. During the 1500-2000 miles, I has no track runs, no racing, just normal week break in driving. $1500.00 lesson.
Just a little food for though.
11-05-2006, 09:10 AM
#10
The LS7 clutch will grab straight off the floor about 1/4 inch to an inch. I noticed that right off the hoist as I was trying to back it off. With almost 2k miles on it now, it's grabbing almost at stock position. It feels great.
11-05-2006, 11:23 AM
#13
Mine was the same way. I think there was only 2-3 others who had had their LS7 clutch installed before me on the board and there wasn't much history on whether it would come up or not. So when I had to turn off the engine to switch gears about to leave the parking lot, I turned right around and told them to shim the slave cylinder. I wasn't going to risk damage and assume it would come off the floor. Yes, there's a bit more free play, but I've gotten used to it.
11-05-2006, 06:16 PM
#14
Another matter for the LS7 clutch is to not use an adjustable master with it. The clutch is self adjusting and will drive you insane because it does so over a period of time.
For any people looking to do the LS7 clutch.
LS7 clutch, LS2 flywheel, 01/02 slave, 01/02 master, replace pilot bearing (I reused my 98 master and it's working fine).
For any people looking to do the LS7 clutch.
LS7 clutch, LS2 flywheel, 01/02 slave, 01/02 master, replace pilot bearing (I reused my 98 master and it's working fine).
11-05-2006, 06:43 PM
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I actually ended up using a pilot bushing for an LT1 (upon the advice of my transmission friend). Same dimensions, and if it fails, it won't take out the input shaft like the bearing will.
11-07-2006, 08:35 PM
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Engagement hasn't moved at all so far, have a good 150-200 miles on it so far... If it doesn't raise up any by this weekend (should have WELL over 500 miles by then), going to put the shim in...
11-07-2006, 10:00 PM
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I'd say at least 1/2 to 3/4 of the miles would be stop and go... Commute to and from work, during times when people just don't know how to drive... Constant clutch work...
11-07-2006, 11:44 PM
#19
Once you are around the 500mile mark with most of it stop/go, I'd give her a bit of highway roll runs.
I eased into mine by doing 4krpm shifts and gradually increasing until I had the 6 krpm shift back.
After that weekend, it was stock again.
I eased into mine by doing 4krpm shifts and gradually increasing until I had the 6 krpm shift back.
After that weekend, it was stock again.
11-07-2006, 11:49 PM
#20
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Give it time. Mine was the same way untill around 600-700 miles. It will start to come up off the floor almost to stock position. My clutch feels GREAT right now and Ive put about 2000 miles on it. I would reccomend this setup to anybody under 450rwhp.