what causes a clutch to not disengage??
#1
what causes a clutch to not disengage??
I just installed a new stock clutch into my car and im having some problems and i have a few questions that the search didnt really help on.
1. what causes a clutch to not disengage??
2. Should the slave cylinder be in contact with the pressure plate fingers at all times? or just when the clutch is depressed?
the answer to number 1 can not be "you need to bleed"...i bought a new master (pre bled) a new slave (pre bled) i did the drill mod, then bench bled the master then bled the whole system over and over and over and over.....
1. what causes a clutch to not disengage??
2. Should the slave cylinder be in contact with the pressure plate fingers at all times? or just when the clutch is depressed?
the answer to number 1 can not be "you need to bleed"...i bought a new master (pre bled) a new slave (pre bled) i did the drill mod, then bench bled the master then bled the whole system over and over and over and over.....
#4
Originally Posted by brad8266
Sorry to ask such a simple questions but there is a throwout bearing in there right? You didnt put your slave in without it did you?
i really dont think that more bleeding will help.
#5
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There are only a few things that will keep it from disengaging and since your setup is new most of those possibilities are gone.
1. Clutch and PP not installed properly or to proper torque values.(possible)
2. Worn disk or PP (new so highly unlikely)
3. Bad slave or TO bearing (new so highy unlikely)
4. bad master (new so highly unlikely)
5. Needs more bleeding. (most likely the case)
I would put it all together and raise the car some and bleed it by using a friend in the driver seat to push the pedal down while you crack the bleeder screw under the car. I did mine like this starting with a brand new and dry slave/master and it took a little over 30 minutes to get it fully bled. Not a single problem with it either.
I know you said you bench bled the hell out of it but i would still bleed it installed for a little while anyway.
1. Clutch and PP not installed properly or to proper torque values.(possible)
2. Worn disk or PP (new so highly unlikely)
3. Bad slave or TO bearing (new so highy unlikely)
4. bad master (new so highly unlikely)
5. Needs more bleeding. (most likely the case)
I would put it all together and raise the car some and bleed it by using a friend in the driver seat to push the pedal down while you crack the bleeder screw under the car. I did mine like this starting with a brand new and dry slave/master and it took a little over 30 minutes to get it fully bled. Not a single problem with it either.
I know you said you bench bled the hell out of it but i would still bleed it installed for a little while anyway.
#6
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Just to throw some more possibilities..
1. Contaminated clutch fluid (rubber, water, oil...)
2. Trans to engine alignment off. This can make the pilot spin the input and look like the clutch isn't disengaging. Make sure dowels are present and all the way seated. Bellhousing is in good shape.
3. Bent fingers on the pressure plate
4. Pressure plate bolts torqued in wrong order causing plate to warp
5. Swollen/warped friction disc due to contamination, overheating, manufacturing defect.
6. Pressure plate surface or flywheel surface isn't flat and has high spots
The short answer is either the slave isn't traveling far enough, the pressure plate isn't properly releasing or all the components are working and there's inadequate clearance between the fw and disc and pp and disc when the slave is at full travel. That's all that would cause it not to release. Most wear type issues related to the PP, FW, and friction disc will result in it not engaging or slipping. The throwout bearing will remain in contact with the fingers on the pressure plate the whole time in most cases. The exception would be after high RPM runs when the PP spinning will tend to pull the fingers outward and push the TO bearing away from the clutch (especially with clutches like the centerforce). This is by design as it causes the PP to clamp down harder right when it's needed, and the TO movement away from the clutch is minimal so that wouldn't notice it in the pedal.
1. Contaminated clutch fluid (rubber, water, oil...)
2. Trans to engine alignment off. This can make the pilot spin the input and look like the clutch isn't disengaging. Make sure dowels are present and all the way seated. Bellhousing is in good shape.
3. Bent fingers on the pressure plate
4. Pressure plate bolts torqued in wrong order causing plate to warp
5. Swollen/warped friction disc due to contamination, overheating, manufacturing defect.
6. Pressure plate surface or flywheel surface isn't flat and has high spots
The short answer is either the slave isn't traveling far enough, the pressure plate isn't properly releasing or all the components are working and there's inadequate clearance between the fw and disc and pp and disc when the slave is at full travel. That's all that would cause it not to release. Most wear type issues related to the PP, FW, and friction disc will result in it not engaging or slipping. The throwout bearing will remain in contact with the fingers on the pressure plate the whole time in most cases. The exception would be after high RPM runs when the PP spinning will tend to pull the fingers outward and push the TO bearing away from the clutch (especially with clutches like the centerforce). This is by design as it causes the PP to clamp down harder right when it's needed, and the TO movement away from the clutch is minimal so that wouldn't notice it in the pedal.
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#8
Originally Posted by myfast70
Or the clutch disk got welded to the flywheel....
it took quite a bit of persuasion to get it free again
#9
Bad, At this point, aside from more bleeding, which you seem to have done repetatively, I would say pull the unit. What clutch is it, or better yet, what disc material is it? If you pull the trans take some pics. I am sure that we can assist in figuring this out.