Help, Slow Shifting at Higher Revs

[YAUDI]

Here a quick summary of what I am getting. At any shift above 4500 RPMs when I try to upshift, it comes out of gear fine, but I have to wait ~1 sec before she’ll engage the gear. I get this in every gear, with no perceived grinding, just the delay at the gate. At low revs (<3500 RPM), the shifts feel pretty much as fast and smooth as normal.

I haven’t played with it as much, but as far as I can tell, the downshifts exhibit the same symptoms. Low revs are good, but high revs even with throttle blips have delayed gear engagements.

When trying to diagnose the problem, there is some noticeable play in the shift cable linkage on the tranny side. There's a steel loop at the end of the cable that attaches to an Al pin/shaft (the aft most located one), where the shaft has a decent groove in it, leaving a few mm’s of play . I’d like to think the cable slop is causing my slow gear engagements. Since I am not getting any grinding, I’d image the syncros still have life. The fact that I get the slow shift in every upshift (any gear), I am thinking something is out of adjustment. I do have the hex shifter shaft, but it still looks alright.

What do the great minds of ET think the problem is ? Dropping her off at the dealer tomorrow, in hopes they know what they are doing and they will listen to my comments about it… TIA...

[Bane]

The clutch may not be disengaging fully either. Could either need adjustment or bleeding.

[YAUDI]

My clutch had what I would consider a very unusual and abnormal failure mode. Don't have the exact terminology, but the clutch assy that bolts to the flywheel consists of the clutch disc, a pressure plate, and a pressure plate mount. The pressure plate and pressure plate mount are attached together with 3 straps that are attached with rivets on each end, fairly typical setup. One of the straps on my clutch assy decided to give up the ghost .

On visual inspection and some quess work, I'd imagine the stress concentrations around the rivet hole proprogated in to a crack that under the cyclic loading fatigue out and tore. Maybe there was some defect or flaw present. Once the strap failed around the rivet, it swung out and became very good friends with the tranny inner bell housing. Not sure how long the relationship was, but I never really heard anything. This really explains the abrupt changed from fine to WTF. Nevertheless, the tranny and clutch are going to be replace under warranty. Not sure if anybody else had run into this, but I hope it's a rather rare failure mode.

Looking at my pressure plate and flywheel surfaces, and the clutch disc, they have held up quick well for 17k miles and lots of lapping sessions. It's amazing how nerve racking this whole ordeal has been so far , I just want to get her back now... The tone from the dealer was so somber, we can't say anything till we get final word, it seemed like I'd get nothing but bad news ... Check out some of the pix and see for yourself...

[YAUDI]

Since there are no doubt people with much more experience with clutches, is this a typical failure mode?

[Irishfan04]

YAudi - Upgrade your clutch while you have the chance (i.e. free labor)!!!

[ducatiexigeowner]

I've replaced many clutches on many different makes of cars
[in my time]...never seen that happen before.
Pressure plate problems, release bearings and oil contaminated clutch
plates are the norm. [noisy spiggot bearings,normaly forgoten]
POOR QUALITY CLUTCH ASSEMBLY springs to mind,like above throw a
decent clutch in it now the box is out.

[Jim Itin]

If you're considering a clutch / pressure plate upgrade, I would recommend
Centerforce. I have no idea if they have a kit for the Toyota drivetrain
(no previous experience with Toyotas, too lazy to do a search of their
website). But I have one of their units behind a Ford 289, and can highly
recommend the performance and quality.
Jim

[Jim Itin]

Yaudi,
OK, curiosity got the better of me, and I checked the Centeforce
website. Yes, indeed, they have a kit for the Toyota 2GZZ. I would
recommend the Dual Friction kit, which is what I put in a 289 motor.
Unless the Celica folks have reasons to not like them, I would think it
will be a good upgrade.
Jim

[codymac]

That's a new one.

Who's doing the work and are you planning anything else while the 'box is out? (clutch? flywheel? Quaiffe?)

[NtflBlueLiz]

Sorry to hear about your tranny problems and thanks for sharing your experiences. Hope you get your Liz back in a hurry.

[YAUDI]

Other than this freak instance, I've been pretty happy with clutch feel, engagement, and how well it's held up in my relatively high track duty. Regardless, thanks for all the comments...

My car is at Overseas, and they seem to be doing a good job at getting her all fixed up ... You local DFW guys are welcome to go peek under her dress and take a look, and tell me what else you might notice...

[YAUDI]

Well, just picked her back up this morning and she feels fabulous. To repair the damage caused by the drive strap failure, a new flywheel, clutch assy and tranny were all replaced. Since I was there, I got the shifter recall taken care of and my flashing starter button. The recal shifter does feel a bit heavier and more robust.

Crazy that it has been almost a month, but getting back in the driver seat it all doesn't matter. Now I got to get her back to the track...

Thank you Lotus and Overseas for taking care of this situation . Great to know Lotus is standing by their product and how we use it ...