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Triumph TR6 - In The Clutches
Yesterday in the midst of an enjoyable 30 mile ride my clutch started to go south and eventually went all the way. As I inspected the usual places the 1st thing I found was an empty hydraulic reservoir, nursed it home (stoplights really suck). I drained and flushed the system completely and refilled with synthetic brake fluid, I seem to have proper slave cylinder extension but still no clutch release. Everything forward of the slave is as advertised, however at the slave the rubber seal around the piston shaft had popped off. Any advice is greatly appreciated the weather is too nice to let it sit in the garage.
Keith 72 TR6
|First off, as I understand it is not good to use synthetic fluid on a system previously using mineral fluid unless you completely rebuild the system with all new rubbers.|
Check the arm release at the end of the slave ie the clutch release arm, if there is no resistance in pulling it back then you have the typical sheared pin situation. This would explain why the rubber would pop out as the slave is trying to push something with no resistance beyond its normal range and thus dumping all the fluid.
If it is this then your TR will be sitting around for a while as you haul out the tranny along with all of the interior. For your sake I hope it is not this...while it is an fairly easy task it is just time consuming and tedious.
The tappered pin along with the thrust washers and diff mounts are the Achilles heal of the TR6...luckily the rest of the car is fairly bulletproof
|As usual Steven has hit the nail on the head.|
However, a british mechanic I talked to recently
when faced with the same problem suggested when
all is apart, instead of putting that badly designed
taper pin back in by itself, weld or braze the clucth
fork to the shaft in addtion to the pin so that the
fork and shaft are one with no stress to the pin
which then just acts like a locator pin.
He said that he had done many like this with no further
|Hey Chris, thanks for the vote of confidence. |
I am not sure however if I would braze the clutch fork on to the rod as this would not allow changing the bushings down the road and with the rod unable to be removed might make taking the tranny appart a difficult thing ie the front end cover holding the input shaft and front bearing.
I think that drilling a hole at right angle and securing a grade 8 bolt with a nylock would be a better modification...and those that are really handy tap a thread at the end of the fork and do away with the nylock using only a lock washer, lock tight or security/safety wire.
beg to differ, but... when I got my TR6 many moons ago, the PO had had the fork welded onto the shaft. I remember thinking at the time what a silly thing that was to do. It is only from the many accounts of the pins shearing that I realized the relavance of what he had done. I think welding the fork to the shaft does have a place in the approved fixes for this type of problem, I just think it has to be done intelligently. Obviously replace those things that will be impossible to replace (other than cutting the shaft) once the welding has been conducted. I think many would agree that the cost of a new cross shaft is relatively insignificant compared to the pain and suffering of replacing a broken pin. If going the welding route, just make sure that the fork is welded on at the correct angle so original clutch action is retained.
|Let me explain my bolt modification...there is a flat round spot on the base of the fork about 1-2cm from the area where the pin goes and makes a perfect spot for drilling (of course in a drill press). Because it is the only flat spot on the fork it makes a perfect place for seating the bolt, it also will have a different orientation than the pin ie 90 degrees|
The new tappered pins are now high-tensile so on their own they are much stronger compared to the OEM that BL used. Coupled with a grade 8 or 10 supplimentary bolt, one will never have a breakage problem. Why spend extra $$ to buy a new shaft every time you want to do a repair and besides I am sure cutting through the shaft will be a pain in the ass. Welds, brazes always have a chance of breaking/cracking and is dependant of the skill of the welder.
Hmmm, think that the bolt mod wins hands down.
my we are feeling a tad competitive, aren't we? I did not endevour to comment on which is the superior fix, merely that the welding fix has it's place. That's all. Also, how many times do you figure on going into the tranny if you did it right the first time? Even with the fork welded to the shaft, I was able to replace the front cover oil seal and gasket (the shaft can be released and rotated). Not a better mousetrap, Steve, just a different one...
|Thanks for the comments, 1st as I was led to understand by the po the system had been rebuilt with synthetic at the same time as the brake system was overhauled. 2nd the operation of my clutch never went totally away it just did not totally release it's engagement. Hence not easy to get into gear at a stand still I guess I will continue to check the hydraulics until I have exhausted that problem.|
I had already assumed u had DOT 5 in the system...I know u know better than to mix:) A clutch usually will not fail that fast and u normally have plenty of worning...clutch slip. The first thing u need to do is exactly what steven said in his second paragraph. Disconnect the slave arm and push on the clutch shaft arm backwards. Simply..is there resistance ..yes or no?...do you have movement before u have resistance? Reading your last post, try this. Have someone push the peddle as far as possible and hold it there. Whith you under the car watch the slave push rob push on the clutch shaft arm and does it hold the arm or does it slowly release back? Do u have fluid leakage? Maybe the rubber seals have gone south. Finally I read an article that the chap was talking about the red plastic hose between master and slave. he said that as the clutch was applied the plastic hose expanded ( I would presume an OE hose) and thus took up the hydraulic pressure and no clutch.... "food for thought".
Good luck Keith
P.S. steven I vote your way on the "upgrade" extra grade 8 bolt....easy to do and is totally removable.
|I replaced the clutch on my 73 last summer and discovered the previous owner had the fork welded to the shaft.|
With the thing welded, there is enough clearance to pull the shaft out of the bellhousing toward the drivers side until the fork hits the inside of the bellhousing. That provides enough clearance to change out the input shaft bearings etc.
The biggest dissadvantage to the welding idea is that the drivers side shaft bushing can't easily be replaced.
The pin and bolt idea is much better in my humble opinion. You drill a hole and add a bolt to the shaft and fork arrangment. It is difficult to beleive that a grade 5 bolt will break.
Here is a question for the board - After replacing the clutch and release bearings and re-installing everything - the clutch now has a different problem -
after the car heats up, say after about 10 minutes of driving, the clutch engagement gets very "sticky". For example, as you let the pressure off the clutch pedal nothing happens and then all of a sudden the clutch engages all at once providing a stall or a chirp. Not fun in traffic. I'v made some sort of error and have to take it appart again, arg.
I changed all the pedal box bushings etc. I think the release bearing sleeve is binding on the shaft. Any thoughts?
|JP--You've got the "sticky clutch" syndrome which is likely caused by a sharp edge on the release bearing sleeve. See the Buckeye Triumph website for the fix (which, unfortunately, involves another gearbox R&R). You may have some luck drilling a small hole in the bottom of the bellhousing to inject some lubricant. I sure didn't.|
That was going to be my afternoon question should the clutch arm have resistance your post would seem to indicate it should I will test this tonight, by disconnecting the slave piston from the arm and moving the arm it assume it should have resistance in it's movement. The clutch never slipped it was replaced by the PO but I wonder about the other internals and what was done I vote for the screw and locknut sounds simpler to those of us without a welding setup.
Re: To weld or not to weld. I've done both successfully. If you are going the bolt route, please ensure that the pin is in, right through the shaft and into the rear of the fork. This may mean removing 0.001" or two off the pin to get it through. The welding alternative is a strong option if you change the bushing prior to welding (chances are, the bushes will last lionger than the gear box).
Also, if there is any corrosion evident inside the slave cylinder, you will not get good clutch release as the hydralic fluid seeps past the rubber seal at the corrided point. Either replace the cylinder or extend the push rod so that the seal doesn't sit over the affected area.
Been there, done that. Far too many times it seems. Thats my 2 cents.
Yes u should have enough resistance...enough that u will not be able to move it by hand in the direction to back of car. If u can move it then get resistance you might have Ignatiouss problem...broken taper pin but still in the fork arm.
It appears to be a personal preference thing on " to weld or not to weld". If u have a welder then go for it. Regardless of the choice do yourself a favour (Bryn mentions above)and that is to double up on the clutch shaft bushs that are pressed into the gear box housing (2 per side). As I have said, Preference for the OE style with the added extra bolt. Keep in mind like steven said, the new taper pin is of considerably higher tensile strength that the OE pin.
|Well after having my 6 sit around the garage since the opening message of this thread, Today I fired it up just to let it run for a while, after checking the valve adjustment and I checked the clutch operation and it is fine. Drove about 20 miles and all is well. I guess I should call her Christine.|
Keith 1972 TR6
This thread was discussed between 21/07/2002 and 10/08/2002
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