manual transmission won't go into gear when cold
 

I've been having shifting issues over the last few months and the problem is getting worse and worse. The car is a 2002 Z06 with about 69k, the transmission was replaced by a dealer under warranty with about 59k.

When I'm starting up for the first time, the transmission won't go into gear at all. When I try to force it, the car will start to roll with the clutch depressed. It takes a couple of minutes of idling before I'm finally able to force it into gear to get going, and when I do get it in gear it doesn't roll with the clutch in. Once it's moving it'll shift but it doesn't feel smooth at all and the effort is definitely higher than it should be with a stock shifter. When I try high-rpm shifting the shifter hits the "wall" and I have to wait for the rpms to drop. Getting it into reverse is the toughest and doesn't get much better even when the car is warm. When the engine is off, I can shift through the gears without much problem except for reverse.

The clutch is a Centerforce with maybe 15k-20k on it, also installed by the dealer along with a new slave cylinder and aluminum flywheel. I had an MGW shifter in for a few years but recently changed back to the stock shifter to see if that was the problem I was having, and since then shifting has gotten more difficult. Most of the clutch fluid is new as I've replaced it through the reservior and it looks pretty clean now.

I tried aligning the MGW shifter using the pin but that didn't help, and it seems like the shaft would go right back off center a bit when I pulled the pin out. Same with the stock shifter. I did re-use the MGW bolts with the stock shifter, and as I recall I needed a couple of washers to make up for the thicker flange on the MGW. Could that be part of my problem? I use AMSOIL ATF and replaced it a little over a year ago, so it only has one or two track weekends on it and not many street miles.

Prior to the past year, I drove the car mostly on the track without any problems. When I started driving more on the street I started to notice it more and it's been getting worse.

What could my problem(s) be and how should I proceed?

If the shifter is moving after you pull the pin then your shifter is not tight enough.

It sounds like a hydraulic issue to me, I would bleed the system and see where that gets you. Hopefully they installed a remote bleeder when they did the clutch!

It wasn't the shifter moving, it was the shaft in the housing that was. It rotated back to the position it was in before I put in the pin. It's not far off but definitely noticeable.


http://i11.photobucket.com/albums/a1...128E0B5609.jpg


I don't have a remote bleeder installed so all I can do right now is replace fluid via the reservior.

Unfortunately that won't get the bubbles out that are trapped in the line. You can bleed it without a remote bleeder but it is a SERIOUS pain in the arse.

You have 2 issues.

The car moving when you force the shifter is indicating the clutch is not fully releasing.

The shifter is not aligned. Keep playing with the adjustment bolt until the alignment holes are aligned. Forget the pin, just loosen it, move it a bit and tighten it again until you hit the sweet spot.

The clutch is not fully releasing because you have air bubbles in the line. A lot of air, if it moves the car forward when you jam it in gear. Take it back to the place that installed it and have them bleed it. It could probably be done with a Motive Bleeder like with brakes, if it is done at low pressure. That would be a lot faster!

He claims it keeps getting worse so how does more air keep getting in there?

Too much air in the clutch line may help explain why it's been getting worse lately. Since the weather is colder the fluid volume may have decreased slightly and it could be just enough to cause the problem I'm having while the car is cold. The heat from the exhaust may be warming it up enough to eventually get the car going. It would be less of a problem in warmer weather. Does that sound like a reasonable explanation?

The clutch and transmission were installed at separate times several years ago by a dealership so I doubt I'd be able to just take it back for them to bleed it. Mike - what is the Motive bleeder that you're referring to? Is there a way to bleed the line without taking out the exhaust and all the other stuff, or do I just need a remote bleeder?

Regarding the shifter - where is the adjustment bolt? I don't remember seeing anything that would allow for adjustment. All I know to do is to use the pin to align the shaft and then tighten the 4 shifter bolts down, but that obviously hasn't worked for me. I had to move the shifter handle around to get the pin in, but even when the bolts are tight the shaft goes back to it's original position when the pin is removed. This happened with both the MGW and the stock shifters. What am I missing?

I really can't see the fluid volume changing due to temperature making much if any difference.

You're adjusting the shifter wrong. The shifter is adjusted via the bolt at the back of the shifter housing that attached the shift rod coming from the transmission to the shifter housing. There is a Torx bolt with a clamp going onto the rod from the shifter housing.

Could be a leak in the system, a seal could have failed in the master or the slave. I had a seal go out on a slave cylinder before, it was all kinds of not fun.

Absolutely. Fluid expands and contracts with temperature. The line going from the master to the slave only holds a few teaspoons worth of fluid at best, so even a slight change in volume would make a noticeable difference.

As far as alignment goes, and forgive me as it has been two or three years since I messed with mine, I believe the position of the shifter box on the torque tube to be just as critical as the alignment of the shifter itself. Do a search on here, I think Bill Curlee has posted the factory instructions for shifter alignment. I would look into the "Anti Venom" mod as well. Until you get your engagement issues fixed though, it is going to shift like crap no matter what.

A motive bleeder is a small hand pump system allowing you to pressurize a hydraulic system and bleed it without needing a second set of hands, or to pump any pedals. Look on Summit Racing's website. I bought one years ago and it has come in very handy for doing brakes on mine and my friends cars.

I'm going to write slower now.

You posted that the clutch has been installed for 15k to 20k miles.

You posted that the the transmission was replaced 10k miles ago.

Now, the clutch is not disengaging correctly.

This isn't something that the shop did wrong 10k+ miles ago when they installed either the clutch or transmission.

So, something is failing. You'll have to pull it apart and try to figure out why when the clutch pedal is pressed that the pressure plate is releasing the clutch disk.

This is likely a hydraulic issue.

You could start with the master since that doesn't require pulling the drivetrain, but you'll still likely have to pull the exhaust and tunnel plate to reach the bleeder.

On another note - you also loosen the two bolts holding the shifter housing to the torque tube to adjust the front to back of the shifter if required. By your picture though, there is likely enough movement in the shifter housing to shifter rod bolt to get it aligned.


So, you think it's a leak? What's the point of bleeding it then? Air won't get into the system for no reason and if you read the OP and the above you'll see that the car has been driven for >10k miles with the clutch installed so it's not an installation issue.

It could be something simple like the bleeder needs to be tightened, who knows. I would bleed it first and see where that gets you, rather than dropping the drivetrain.

Google Youtube "motive bleeder clutch c5 corvette." It will show you how to bleed the clutch without taking everything apart. Be careful with the amount of vacuum used so you don't blow the seals. It can be done with one person but it is easier with two. If you cannot find a satisfactory view, send me a pm and I will email you an instruction sheet.

Correct... :thumbs: I pulled up the shifter adjuatment procedure and,,,

Shift Linkage Adjustment
Adjustment Procedure




Apply the parking brake.
Remove the shift control closeout boot. Refer to Shift Control Shift Closeout Boot Replacement .
Place the shifter into NEUTRAL.
Press down to engage the shift control neutral lock pin.



Loosen the transmission shift rod clamp bolt.
Loosen the shift control mounting bolts.
Check that the shift control locator (on the underside of the shift control) is installed into the shifter bracket on the side of the driveline support assembly.
Tighten the shift control mounting bolts. Tighten
Tighten the shift control mounting bolts to 30 N·m (22 lb ft).


Notice
Use the correct fastener in the correct location. Replacement fasteners must be the correct part number for that application. Fasteners requiring replacement or fasteners requiring the use of thread locking compound or sealant are identified in the service procedure. Do not use paints, lubricants, or corrosion inhibitors on fasteners or fastener joint surfaces unless specified. These coatings affect fastener torque and joint clamping force and may damage the fastener. Use the correct tightening sequence and specifications when installing fasteners in order to avoid damage to parts and systems.


Tighten the transmission shift rod clamp bolt. Tighten
Tighten the transmission shift rod clamp bolt to 30 N·m (22 lb ft).





Lift to release the shift control neutral lock pin.
Install the shift control closeout boot. Refer to Shift Control Shift Closeout Boot Replacement .
Release the parking brake.

--------------------------------------------------------------------------------
Document ID# 211052
1997 Chevrolet/Geo Corvette


Recommend that you spend the time to either properly bleed the slave and master with the stock bleed valve or while your down there, install a remote bleeder line and bleed the system that way.

Hydraulics is the first suspect. Until you bleed the system, your not going to be able to eliminate that as the problem. I agree with lionel, After you bleed the system, If that doesnt work, replace the master cyl.

Another recommendation is NOT to force the transmission to shift. You are doing damage to the synchros and cones.

Bill

Guys - thanks for all the info. I dropped off the car at LMR on Thursday for a re-tune and they are going to bleed the clutch next week. After I get it back I'll try adjusting the shifter to see if that helps. I can't get to my shop manual right now but reading the instructions posted it looks like I may have skipped one or more steps when swapping shifters. All I did was remove the 4 bolts during the swap, I didn't touch anything on the shifter box. I'm (obviously) hoping that bleeding the clutch fluid fixes the problem I'm having getting the transmission into gear when the car is cold. The slave cylinder was replaced with the clutch but it's seen a lot of track miles so who knows what condition it's in.

Well I got the car back from LMR and I've adjusted the shifter, but the clutch problem is still there. I can't really get a good test drive to check the shifter because of the clutch problem, but the holes are aligned and the shaft stays in place when I remove the alignment pin so I feel good about that.

They said they did bleed the clutch fluid and that it was better briefly but that the problem quickly returned. Is it possible that they just didn't bleed enough of the fluid and that it needs to be flushed more thoroughly? If so then I'll take it back by there but I don't want to waste time if that's not it.

I've searched the forum for clutch bleeding methods and the only one I found that's different from the service manual method involves removing the intake manifold. Is that the quickest way without a remote bleeder or is there any other way to get access?

If I need to move on to the master cylinder - would it be leaking fluid somewhere that I'd be able to see without removing the exhaust/tunnel plate/etc? Is there a way to confirm that's the problem before I actually replace it? And if I have to replace the master cylinder I'll still need to bleed the line from the port at the slave cylinder, right?

Won't really leak or indicate any problems other than the clutch won't fully disengage. Had a similar problem on my 02 at Watkins Glen in July 11 and had to run a race mostly without the clutch which wasn't fun. Replaced everything in the tunnel when the engine was out - no change. Replaced the master cylinder for the first time ever - fixed it. Was a pretty easy change. Brother-in-law and I did it in about an hour. Helps that we had previously installed a remote bleeder line. Without the remote bleeder line it is possible to get a small wrench on the bleeder once you remove the tunnel plate, but it is a PITA. Remote bleeder line one of the better mods I've done. :cheers:

I went ahead and ordered a Tick master cylinder. Figured I may as well upgrade while I have to replace it, but I didn't realize how much more work is involved compared to just replacing it with a factory MC. Hope it's worth it!

Recommendation: Pull out the drivers seat, get in the car laying on your back with your head under the dash and feet in the rear compartment. With a good light, you can see everything and get to everything!! That for me, made the job a hell of a lot easier!:thumbs::rock::cheers:

BC

Another possibility
 

A failing pilot bushing/bearing can have symptoms that mimic a partially engaged clutch. The crankshaft can transmit torque to the input shaft via a failed pilot bushing/bearing in much that same way that a dragging clutch would.

Ohh,,,, EXCELLENT recommendation!!!:rock: Didnt think of that.. If the pilot bearing was bad it can also make noises and cause weird vibrations.

Excellent info!!

BC

Would a bad pilot bearing make a rattling noise when the clutch pedal is out that goes away when it's pushed in, and would it cause vibrations in the clutch pedal that can be felt with light pressure on the pedal? I do have my carpet and sound deadening out so it's pretty easy to hear all the noises the car makes - not sure if that's a normal one or not.

I got the Tick master cylinder installed (PITA as expected) and the car is drivable now. However, there is still slight but noticeable movement when I put it in gear before I let the clutch out. Not nearly as bad as before but still there. I've only bled the system using a Mityvac in the reservior for now and don't see any bubbles, but I'm going to try this method as soon as I get a chance just to be sure:

http://forums.corvetteforum.com/c6-c...errerid=178898

I also plan to adjust the master cylinder to see if that helps. I want to extend it to (hopefully) cure this problem, right?


If the next two steps I have planned cure the problem with the car creeping with the clutch in, does the rattling and pedal vibration I can feel indicate that I have yet another problem, maybe with the pilot bearing as mentioned above? Or if the creep problem goes away, are the other issues not significant enough to worry about?

Well I bled the system using the syringe method which worked pretty well. I got several bubbles out and lots of nasty black stuff, emptying and refilling the reservior with the syringe 6 or 7 times until the fluid coming up was clean.

I fired it up and when I put it in gear with the clutch in, the car still jumps a tiny bit as it goes into gear. It doesn't keep moving if I sit there with the clutch in, it's just a little nudge when it first goes in and then it stops.

Does that sound like something I can fix by adjusting the master cylinder rod length? I'll want to extend the rod and try again, right?

You dont want to overextend it but see what happens with a 1/4 turn at a time up to one turn. I would expect a change.

That would indicate your transmission isn't spinning down. As a test, when you disengage the clutch (pedal down), count to 10, then engage a gear. If you still feel that little lurch, then your clutch is likely dragging slightly.

I agree. If that is the case, theres a possibility that the clutch disk hub is slightly bent (can happen during reassembly if the installer wasn't careful) causing the clutch to never fully disengage..

Yeap, or the slave is leaking and contaminating the friction surfaces. Both of those happened to my last clutch. :banghead:

You should adjust the master following the instructions from Tic plus possibly a little more as indicated by Bill. Don't just go wild changing the length.

Thanks for the responses guys, I'll give all this a try this evening and report back. Fingers crossed!

Curious to this as well. My clutch makes some noise/vibration when i release the pedal in neutral. Is the pilot bearing different from the throwout bearing? To my understanding they were the same? Mine's been making this noise quite awhile now and I have a new throwout bearing on it.

Pilot and throwout are 2 different things. The pilot bearing is in the end of the crank and it supports the input shaft when the clutch is depressed. It's very unlikely the pilot bearing is making noise when the clutch is released since the crankshaft and input shaft are both turning together.

So I worked on the pedal last night. I adjusted a few turns and fired up with no change. Then I figured out that the master cylinder rod isn't supposed to turn along with the link so I held the rod with some vise grips and turned the link. All I was doing then was un-threading the link from the rod so that didn't work either.

I re-threaded the link onto the rod, took the heim joint off the pedal and turned that while I held the master rod and the link. That visibly worked so I went to try again, and of course the car wouldn't start and I got a charge system fault message on the DIC. So I left a charger on overnight, but it still wouldn't start this morning (though no error from the DIC). In both cases the starter never turned over, I just got a few light clicking noises that sounded like electrical switches.

Is it possible that since the pedal position is changed, it's not hitting the sensor on the firewall that says the clutch is depressed and lets the car start? The clutch pedal is now just a little higher than the brake pedal, which is where the guy at Tick said to put it (I called yesterday afternoon).

This is seriously frustrating. :banghead:

Yes, that is probably what is happening. You've adjusted the MC pushrod so far that now you're bottoming out in the cylinder and hence not hitting the clutch interlock switch. The switch is easy to see on the floorboard. Just back off the adjustment on the pushrod until you're fully depressing it.

Ok will do, thanks! I'll report back on how it goes.

I got everything adjusted and the car runs much better now and I can shift ok just driving around. If I push in the clutch and wait a couple of seconds before putting it into gear, then it doesn't move, but if I put it in gear right away it still does a little bit. I've adjusted the clutch pedal out to just above the brake pedal per my discussion with Tick. I can shift at high rpm better than I could before, but I wouldn't say it's smooth - it definitely still takes some effort even with the stock shifter.

Considering all this, should I assume that I'll be having another problem sometime soon as long as I keep driving it? It's nice to at least be able to drive it around for a while finally!

allot of great advice here.

I'm having the issue where the car doesn't really want to go into reverse. It "chiks" when I put it in and a few times the car still moves back when it's NOT in reverse anymore and have the car in neutral and let out the clutch.

Was hoping it's something kinda "easy" ( not replace/rebuild tranny or replace clutch yet. )

Sounds like you have a synchro issue and or a shift fork pad issue. If the pads are damaged, the shift fork cant fully engage the slider over the gear.

Check out this post. The reverse gear and all the reverse parts ar in the rear section of the transmission. You can actually fix it without fully disassembling the trans:

- C5 ragtopws6, T-56 Build (whats in my tranny?) : http://forums.corvetteforum.com/nort...-smoother.html



I also added a couple of cool rearend build post too
- C5, ragtopws6 , Upgrading your C5 rear with C6 Z06 guts, : http://forums.corvetteforum.com/c5-g...-z06-guts.html
-

- C5, Its_Go_Time, Output Shaft Install - Left and Right: http://forums.corvetteforum.com/c5-t...post1573407966

well, that seems certainly beyond my means and talent. I adjusted the shifter last night and it seems at 1st glance to have helped a lot. I had this happen when I first bought the car back in 08 and I had to do that before, so I HOPE this will fix it.

If not, then I guess I'll be looking for a shop I can trust to look into it over the winter.

Ancient thread, sorry to resurrect but it matches the symptoms of my 2003 Z06 with 112K miles exactly - when I first start car, impossible to get into gear. If I pump the clutch and force into gear (need to be careful with this) then the car will move even with clutch fully depressed. It will try to move more and more until it finally dies (brake depressed) even with clutch fully depressed. If I pump the clutch ten times or so, it will shift better. When driving, even when warm, I would say it never shifts that great and if trying a quick 0-60 run under hard power first to second is like a second long shift - it just won't go in.

This is a new to me C5 so hoping it's not too bad, like a new transmission needed. Prior owner did say he installed - apparently self installed - a Stage 3 Monster Clutch. Maybe incorrectly? Clutch fluid looks clean in reservoir but I have not performed a flush yet.

From reading above it seems the clutch bleed/clean/flush perhaps contributed the most to the recovery? Or was it the after market slave cylinder? Not clear what led to the most improvement. But what was happening hear sounds just like what mine is doing. Any more recent experiences welcome, will update at some point when I get this fixed with what worked for mine.

@NewFoundPower

Hi, I would guess that it's a clutch problem because before I got it fixed the clutch came apart and destroyed the bell housing. This happened on the street on the way to work not long after I posted this. Granted it was at full throttle and shifted 1-2-3 pretty quickly since I had a good straightaway at the time. Luckily I was able to coast to the parking lot. Replaced with LS7 clutch and aluminum flywheel and the problem was gone. I can't believe I still have pictures but there they are below.

https://cimg9.ibsrv.net/gimg/www.cor...9ba1a7ba1c.jpg
https://cimg5.ibsrv.net/gimg/www.cor...063ee0781c.jpg
https://cimg9.ibsrv.net/gimg/www.cor...a1c8e82010.jpg
https://cimg1.ibsrv.net/gimg/www.cor...11f8967076.jpg
https://cimg2.ibsrv.net/gimg/www.cor...807712994b.jpg
https://cimg3.ibsrv.net/gimg/www.cor...0b48dcb0f4.jpg
https://cimg4.ibsrv.net/gimg/www.cor...07e24d5061.jpg
https://cimg5.ibsrv.net/gimg/www.cor...f97c167416.jpg
https://cimg0.ibsrv.net/gimg/www.cor...e2797f17c9.jpg
https://cimg2.ibsrv.net/gimg/www.cor...fd515e63ef.jpg
https://cimg4.ibsrv.net/gimg/www.cor...e7ce11110d.jpg

wow I had CF also never again. Where did u find bellhousing??

Same here on the CF.

I had it towed to LMR straight from work and had them do the clutch replacement, so I didn't get to go back over the road where it happened. All of those parts were in the pile they gave back to me so somehow they stayed together.