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ls7 clutch problem??

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Old Dec 6, 2008 | 11:04 AM
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Default ls7 clutch problem??

I just installed my ls7 clutch{1700 miles ago}did the break in,the clutch felt great,fell wright where its supposed to:about 1/2 way @450 miles ,now at 1700 sometimes the pedal feels empty at the top,and the clutch engages right off the floor,fluid looks ok{alittle blackish}/its not slipping.then other times it goes back to where its fine,They're are no burnout or hardshiffting on this clutch.any ideas??going to rebleed this week to try that,well see.
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Old Dec 6, 2008 | 02:38 PM
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try replacing the master cylinder
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Old Dec 6, 2008 | 02:51 PM
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Similar miles on my LS7. Mine has had a very low engagement point since I put it in (typical from reading posts here). I think it has moved up a little from where it started but not much.
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Old Dec 6, 2008 | 03:23 PM
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Originally Posted by massls1guy
Similar miles on my LS7. Mine has had a very low engagement point since I put it in (typical from reading posts here). I think it has moved up a little from where it started but not much.
Have you had the empty pedal feel at the top?good 3" or so
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Old Dec 6, 2008 | 04:21 PM
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Originally Posted by johnnydje
Have you had the empty pedal feel at the top?good 3" or so
I'm not sure what you mean by empty pedal feel - I guess my answer there is no. My pedal feels the same as stock besides engaging close to the floor.
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Old Dec 6, 2008 | 04:28 PM
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I'd go with door number 1 thru 1 billion... ie its almost always a hydraulic issue.

Key notes: blackish fluid, pedal engagement near floor, empty feel near top of pedal.

near floor should be alarms flying off in your head that something is seriously fubared. That means when trying to release the clutch, you need to all but use the ENTIRE master cylinder's volume to disengage it. Even then you are not guaranteed a complete disengagement. Stop driving, bleed the system. If it doesn't return to normal ie around 1/2 way and stay that way, I'd check for leaks. The master test is the easiest, disconnect the hydraulic line from the slave, try to push the pedal, if the pedal isn't rock hard and allows a good amount of movement, the master is faulty. If it stays rock hard, its the slave.

Sponsor pimp ahead: Get the tick master if its the master.
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Old Dec 6, 2008 | 07:14 PM
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Originally Posted by SladeX

near floor should be alarms flying off in your head that something is seriously fubared
Low engage point on an LS7 clutch is very typical from posts that I've read.

You're probably right that he has some hydraulic problem.
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Old Dec 6, 2008 | 09:18 PM
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Low engagement for the LS7 happens during break in, but moves itself up within the first 100 miles. Since he said 1700 miles, I'm pretty sure those weren't all highway miles...
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Old Dec 6, 2008 | 10:30 PM
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I finished the clutch install about 3 weeks ago and I have over 1500 miles on it. Maybe mine's slow to break in because I drive a lot of highway miles.
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Old Dec 7, 2008 | 01:05 AM
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Hydraulic issue
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Old Dec 7, 2008 | 07:04 AM
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Originally Posted by massls1guy
I finished the clutch install about 3 weeks ago and I have over 1500 miles on it. Maybe mine's slow to break in because I drive a lot of highway miles.
Think your supposely to mix it up,stop-n-go traffic too.mine fell right in about 400-450 miles
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Old Dec 7, 2008 | 07:06 AM
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Originally Posted by letsrunem
Hydraulic issue
Thats what I figured,going to rebleed it first,then see what happens.hope that does it.
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Old Dec 7, 2008 | 09:02 AM
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Mine broke in within the first 60 miles, traffic jam, on a bridge for 40 mins, stop and go a few feet at a time for a few miles, by the time I made it to my destination, pedal was 1/2 way and my clutch leg was cramped to hell.

I drove an additional 120 miles after that, 80% highway, but it never moved anymore than that until I swapped out my master to a newer piece which moved it up a bit more.

Highway miles mean nothing for the clutch break in because its NOT slipping. Think of the break in period as similar to brake pads. With brake pads, you do short stops getting material on the rotors and slowly work your way up to higher speed stops, but not putting in full stopping power until then. The clutch has to do the same thing, but it is the opposite of a brake system in that its always engaged. The only time it has a chance to break in is when you are just engaging it ie from a stop. Higher speed shifts are like the high speed stops and you don't want to do that till later in the break in as you will not get even material distribution onto the flywheel/pressure plate that way.
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Old Dec 7, 2008 | 09:24 AM
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I thought right off the floor was normal too..From what i read Amber at six speeds inc. told me otherwise. Had my trans rebuilt and got a new slave. Found out my old one was sticking. Now it engages half way out or 5-6 in off the floor where its suppose too.
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