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Clutch disengagement issue

9.7K views 27 replies 10 participants last post by  RC51 Coop  
#1 ·
Me and another CelicaSupra member, Turbosidosis, swapped a w58 into my car over the past few weekends, but we are having a problem with it shifting. The car is a 85 with a 5M and W58, and I am using the S3 short shifter. The flywheel was resurfaced and a new nonturbo 7M Exedy clutch, pressure plate, throw out bearing, and pilot bearing were installed.

The transmission will shift through all the gears alright with the engine off, but once the engine is started it does not want to go in gear. I can put it in first gear, start the engine and drive it as normal, but still wont want to shift. Also, when in first, the car will creep a little bit like an automatic. So, I believe the clutch is not disengaging all the way. The master cylinder is full, and it nor the slave are leaking. I get plenty of throw on the slave and I also adjusted the clutch petal. We greased the clutch fork, throw out bearing, and also the transmission shaft. I worked the grease in well on the trans shaft and I made sure the clutch disk moved smoothly on it.

I really feel it's the grease on the trans shaft that is causing this. =[ Does anyone have any ideas of what may be the problem or how to fix it!

Thank you!
 
#2 ·
Wont go in gear as in its grinding trying to go into gear?? Sounds like the pressure plate isnt releasing the disc all the way>>>Clutch disc in the correct way??
 
#3 ·
Sound like it is a problem with the master, slave, or the rubber line. This happened to me once when the fitting on the end of the SS line had failed.
 
#4 ·
How long is the metal rod that the slave cylinder pushes against the clutch fork with? I've had to make longer ones out of bolts before to get the clutch to push in farther and thus shift correctly. It also sounds like either a bad slave or master cylinder.

I'm going to assume that people who can remove a transmission are smart enough to bleed the clutch from the slave cylinder correctly so there are no air bubbles in the system.
 
#12 ·
Im with Dave-My car has a 3 times resurfaced flywheel, and this last time I had to "fab" up some extra throw at the slave.
 
#5 ·
you didnt mention your bleeding procedure for the master, how did you do it.
 
#10 · (Edited)
Just adding support for the clutch master, slave or lines being the culprit. I had this problem a week ago. Turned out my master cylinder was starting to go - could see it starting to leak out of the piston and down the pedal / firewall. I imagine you'd have the same issues with air in the system though, which is probably reasonably likely if you've been doing work on the transmission.
 
#11 ·
Hey guys, thanks for all the input. I really don't think it's the master or slave. All we did was a transmission swap using a transmission that shifted great before. I don't see why bleeding the lines would be necessary since we didn't disconnect any of the lines, only unbolted/bolted the slave cylinder. I watched the throw on the slave cylinder as my friend pumped the petal to make sure the slave was working propertly. I would like to get back to the car this weekend, measure how much throw we are getting and compaire it with you guys. This is my first time to install a w58. I'v only done the r154 a bunch of times.

I am interested in the disk being on the right way question. I specifically remember making sure the springs and area that bumps out was toward the pressure plate and not the flywheel. I assume there is no way to check that without taking the transmission back off. =[ I'm really starting to like those bellhousing access panels on the r154. Is there anything specific needed when installing the clutch fork on a w58?

Thank y'all for the help!
 
#17 ·
sorry If I'll be rude, but you just answered your own question in your response here. You unbolted the slave cylinder, re bolted it, then watched it functioning properly, without bleeding it. If there is air in there, when you put pressure on it the air is going to compress in the line and your clutch is going to stop working. Did you turn the reservoir upside down at any time while you swapped it over? Re-bleed that line, many times until you are sure. Make sure the nipple on the slave doesnt have shit blocking the hole before you try.
 
#15 ·
OK NOW You guys got me thinking, because I am very near a transmission swap of my own and I don't want this to happen to me. I don't want to call anyone out or anything. Just looking at this as a learning experience for me. I got a W58 from an 83 GTS at Pick-N-Pull recently and was going to swap it out in the near future because my current trans has been bad since I got the car. Although I don't actually know anything about this trans I think it will be an improvement if there are no other issues that go along with it (it was originally hooked to a 22RE), so I am very interested in this one.

Well then here is what I get:

You say the clutch pedal, master and slave are good because they were never touched (just unbolted and rebolted).

The Transmission is good (or at least it was and still should be).

Then it seems to me there is really only one thing left.... the clutch.
Since it is not working correctly how many things can it be? Either 1) it is on wrong or 2) it just doesn't move enough to disengage properly.

If it is on wrong:
How did you determine the following clutch disk orientation?

I specifically remember making sure the springs and area that bumps out was toward the pressure plate and not the flywheel.

Is that how the "old one" came off??

Since JQ said it "acts like an automatic" I assume he means the car moves when it is in neutral with out the brake on... so the clutch seems to be "engaged" slightly when it shouldn't be. If you got the flywheel resurfaced, it CAN'T be thicker so it should be harder to make it engage not the other way around.

If The clutch doesn't move enough:
you like the pedal travel, master and Slave and think they are OK

So what else can affect the travel?
The clutch fork might be the problem also. Is it on the pivot point correctly? If the clutch fork was not on the pivot point correctly the slave could have enough throw but still not be disengaging the clutch disc

Like I said I don't want to fight, I just want to help get this right.

Good Luck keep us informed
 
#16 ·
If you got the flywheel resurfaced, it CAN'T be thicker so it should be harder to make it engage not the other way around.

.

Good Luck keep us informed
The clutch disc is oriented with the spring cage towards trans. Flat side to flywheel. An over surfaced flywheel INCREASES pedal travel needed to dis engage clutch. Remember, clutch is engaged until you push pedal. Im taking the "acts like an automatic" statement to mean it moves with the car in gear, and clutch pedal on floor...Please correct me if I am wrong at all here..
 
#18 ·
and what type of clutch are you running, the pedal height changes with different types of clutch materials/construction
 
#19 ·
The clutch is a new nonturbo 7M Exedy unit. We did not mess with the master and I hung the slave to the frame with some string. I understand what all of y'all are saying and I have lots of things to try now when I get back to the car. I don't know the full life of this flywheel so it could be resurfaced just enough that I ran out of throw, or the slave cylinder has a wear spot and is not going its intended full stroke on a new clutch, some air developed in the line, or there is something different about using a 7M clutch. I don't think the clutch disk is hanging up on the flywheel bolts because we don't get any noise and I am able to hold the car at a stop with the break while in gear and the clutch petal depressed without the engine dying. So, the disk should be installed in the right direction.

Regardless of what I think, we will bleed the clutch first then if that dosent fix it right off we will move the clutch fork to its maximum throw and see how it shifts, to make sure it is a slave throw issue. Then we will decide if we need a new slave or shim the old one.

Lots of discussion in this thread I had never really thought about before.
 
#21 ·
Well, we are back at the car today messing with it. We have done all our testing and messing with it and nothing has helped. When I artificially push the clutch fork as far back as it will go, making it touch the bellhousing, the clutch is still not disengaging all the way. While looking at it I noticed that the clutch fork is really close the bellhousing even at rest. What I mean is that when the fork and throwout bearing are just resting up against the pressure plate there is only about 3/8 of an inch of travel until it would hit the bellhousing. I think the fork needs to be closer to the slave cylinder when no pressure is applied. So we are only getting about 5/8 inch of throw from the slave. I think there is a problem with the fork / throw-out bearing assembly. Does anyone know where the fork should be positioned at rest? Here are some pics to show what I'm talking about:

Image

Image
 
#22 ·
I never asked what the W58 came out of, and if you used the Supra belhousing/fork/fork ball from Supra...my bad.
 
#24 · (Edited)
The TSRM only lists a runout spec of .008, with no mention of depth specs. Shop "should" have that spec available. I dont know how many turns flywheel has had. An entire tenth seems excessive. Edit-I dont think its flywheel after seeing your pics-that looks like bent fork/throwout blocked like you said.
 
#25 ·
well we got the girl running. We used the new 7m exedy clutch, with the my old 5m exedy pressure plate, and the new 7m throwout bearing. We also notice that the spring on the throwout bearing could be switched to the other side, so we did that also.
She shifts smoothly through every gear, and there was no need to turn off the car and put her in first and start her up from previous attempts.
again, thanks guys/gals for the info and help and much much love and thanks to my buddy John!