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bash
04-05-2006, 10:19 PM
I just finished rebuilding the hydraulics for my clutch (TR6) and I found that someone had "doctored" the slave cylinder push rod - when the replacement arrived today I compared the two and found that the one I took off the car had nearly 1.5 inches added to the end... I remember reading one of Nelson Reidel's articles where he descirbed a similar "modification" and it turned out to be a broken fork pin at the root of the problem. I am pretty much sure that I will be ordering some clutch parts and pulling a gearbox in the near future, but wanted to check with those who have experienced the problem first.

I haven't really driven the car, though I have moved it around using the engine and the clutch worked fine. I know that I wasn't asking much of it, but it didn't seem unusually heavy or like it wasn't engaging as I would expect. Would that be the case with a broken pin?

I cannot move the lever on the cross shaft backwards at all by hand. Should I be able to make it move? It sits roughly vertical at what seems to be the rearward extent of its travel. It will rotate towards the engine with minimal effort, and I suspect that if I install the new push rod it will be moving in this very low effort part of its travel - is that possibly the right arc of movement? I am clinging to the idea that the badly worn clevis pin at the pedal could have caused enough slack to make the PO decide to weld a length onto the slave push rod!

I was doing so well ticking off items on the list I made last summer when I bouhgt the car, and I was looking forward to driving in the next few weeks - I will be very pleased if someone can reassure me that the clutch doesn't need work just yet! Thanks in advance for your replies, even if you are just confirming what appears to be the inevitable!
Alistair

DougF
04-05-2006, 10:27 PM
The lever should not move by hand backward. If so, you would be having problems(probably fork pin). It should move forward a short distance and stop. This is the throw out bearing sliding up the input shaft.
I had a make shift extension one my first TR6 at purchase. Found that the slave cylinder bracket had been mounted improperly, losing about an inch or so of throw.

bash
04-05-2006, 10:50 PM
Thanks for the quick reply, Doug. I have attached a picture (well, I have tried...) of the slave cylinder (before I took it off to clean up and fit new seals) - does it look about right? What was mounted incorrectly on yours?

Thanks again,
Alistair

DNK
04-05-2006, 10:55 PM
Its been a while but shouldn't it be in the middle hole?
don

bash
04-05-2006, 11:05 PM
Hi Don

I realised that when I was taking it off - I didn't notice the extra length of the rod until I got the slave cylinder apart, though. When I saw the top hole being used I figured it was the result of the really badly worn clevis pin I had just struggled for 20 minutes to remove at the pedal!

The slave mounting bracket is on the engine side of the gearbox flange - if that was on the wrong side it would make everything look a lot better, but it doesn't look like it will fit on the other side to me. I've attached a picture from a slightly different angle this time - I am really hoping that someone will see something I can fix easily!!

Alistair

DougF
04-05-2006, 11:06 PM
My slave cylinder was actually mounted to the front side of the bracket, so I lost the widths of the bracket and the slave.
Yours is mounted properly.
Maybe this person didn't like where the clutch was releasing at the pedal and attempted to adjust it at the rod. That's the optimist in me thinking. But I've see dumber things.
The rod usually is mounted at the middle hole of the clutch shaft arm, but as things wear and you lose pedal, the top hole comes in handy.

04-06-2006, 05:31 AM
Alistair,
If your slave cylinder apparatus has been refreshed (rebuilt or new), and the proper length rod has been used and attached to the middle hole of the cross shaft arm and the clutch doesn't work properly, you will be pulling a tranmission. There is very little room for error in this setup. Sounds as though your pin on the cross shaft has sheared. If and when you pull the tranny, don't scrimp when replacing parts. A new cross shaft assembly is not expensive. This would also be time to make a decision about a new clutch and throwout bearing. And inspect your ring gear and flywheel. Yes, pulling the tranny is a real PITA but doable by one person with a good set of jack stands. You know that much of the interior has to come out and the tranny goes north. I have done this 3 times and am looking at a fourth (chipped some teeth on the ring gear). Bottom line, if the slave cylinder has been rigged, something is wrong. Sorry to bring the bad news.


Bill

trboost
04-06-2006, 07:20 AM
Hey Alistair,
No need to get upset, many of us have been there. Pulling the trany is not rocket science just grunt work. The more organized you are the better this works. Even a novice can remove the interior & trany in an afternoon ( Three hours when you do it as often as I ,believe me , I'm not proud ! ) If you are in a position to have it done for you & have a reliable shop ther's nothing wrong with that either. After all is said & done you will far from miss the driving season. The most time consuming part is removing the bell housing bolts, it's awkward & some of them are tough to get at. A second helper holding a wrench in the engine bay would speed this up ( especially during reassembly ). Whether you do it yourself or have it done you should be driving in a week.
As Bill said, now would be the time to do it right. This is a parts replacement fix, no machining except for a secondary fork pin which is an easy repair ( pic attatched).
The extension of the slave cylinder push rod is a dead give away that the PO was trying to compensate for a problem. Excessive pedal box play would account for some lose of movement but not that much.
Before you start the repair just check that the slave cylinder rod moves a minimum of 5/8" . The TR6 slave cylinder is self adjusting and that is why the older style adjustable push rod isn't used. You also mention that the clutch works but dosen't "feel" right. If the pin is broken very often it shears at one spot leaving the tip of the pin binding between the rod & fork. This usually leaves a vauge feel to the pedal & requires the use of the top hole on the lever arm. Eventualy this last bit of the pin shears causing full lose of pedal. There isn't much else in there that can give that kind of feel other than a faulty pressure plate & at that point you would have to do a service any way.
If this is done properly you should never have to repeat this repair & the car should give you much more clutch reliability.
If you want to do this your self let us know and some more tips & pointers will follow.

bash
04-06-2006, 08:04 AM
Thanks a lot for the replies, guys. Great advice, as usual!

I will head into the garage today to check that the new rod doesn't work, but I am fairly certain that I will be doing the clutch work. Any tips and advice you could offer would be appreciated - I am determined to do all of the work on the car myself, but I am certainly not too proud to take advice!! I suppose I should be thankful that I put off putting in the new carpet last month - my interior is pretty much out of the car anyway, so hopefully it won't be too hard of a job. TRF has the fork, shaft etc. on sale for $75 at the moment - is it worth picking up all of that stuff new, or will the old one be just as good? Also, I guess I will wind up replacing the clutch while I am in there - I know that there are good and bad brands - anyone have any recent experience? The 3 piece kit from BPNW for $130 looks tempting, but not worth saving the money if it will give me problems.

Thanks again
Alistair

trboost
04-06-2006, 08:30 AM
After you check & have commited to doing the work I know both TRF & BPNW offer Gunst or Gunst style bearings. Both should come with a bronze carrier. Highly recommended. Also order a new set of clutch shaft bushings & double them up , pressing two on each side. You might even want to check & order a rear trany seal.
I think any of the clutch option packages will work fine but I'm sure many have their preferance. MAKE SURE the two bell housing dowel pins are present, if not get them. This is the differance many times for proper clutch operation & they are often disposed of & bolts put in their place.
Get lots of zip lock bags & be anal about seperating and organizing bolts and parts. Even a digital camera helps jog the memory & documents your work and for later pats on the back when you relive the fun!
I like to drive the car up on to ramps in the front. This give me enough access to the underside with out having to jack the car up. You will also have to get a jack under the oil pan of the motor to first support it & later to adjust it up/down to align with the trany. The transmission acts as a support for the back end of the motor.

Have fun

ROADSTR6
04-06-2006, 01:16 PM
You might want to consider cross-drilling the shaft and fitting a bolt as a stop gap measure if the new pin decides to break. I did that. Some folks even weld the fork to the cross shaft. That seems a bit extreme to me because you'd have to cut the cross shaft into to get it back out if the need arose. At one time there was a problem with the pins the major suppliers were offering. They didn't fit properly and many broke within days of replacement. This problem may be resolved now, but that may be reason enough to go with the bolt and pin method. Good luck. I feel your pain. You'll get it done. As was said already, it's just grunt work. No rocket science involved.

Dave

Geo Hahn
04-06-2006, 06:41 PM
I too used the added bolt for better security against a future break. I use 1/4" grade bolt of appropriate lenghth with a self-locking nut.

If oyu pull the gearbox the one special tool you will need is that clutch alignment tool or an old input shaft to line everything up for reassembly.

Since you got no replies to the contrary to your photos I guess your slave is mounted correctly (flange behind the bracket?). On TR3s & 4s they mount with the flange to the front of the bracket.

I wouldn't rule out the possibility that all is well -- I would certainly mount up the slave with the correct push rod into the middle hole and see what clutch action I get.