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GuyShark
06-16-2006, 07:26 PM
Ok, please help!

I recently purchased a 71 TR6. Its in really great condition.
I drove it 3+ hours home, and everything was great. The next day I take it out for a spin, and all of a sudden, I cannot shift. Ok, check the clutch fluid, it was very low.

Bled the system refilled, still no shifting. VTR.org states that if you can get 5/8" of lateral movement from the clutch rod, then that is not your problem. Ok, I was getting that.

Next step? Pull the transmission. So that is where I am.
Seats/interior is all out. I am trying to use the Haynes manual to help. I have all the bolts free around the bell housing. The main bolts, and the driveshaft bolts are all out. The transmission is still not moving! The driveshaft is still pressed up against the transmission, so I cannot pull the transmission back at all.

What am I forgetting to do?

TIA

Harry_Ward
06-16-2006, 09:58 PM
I do not own a 6 but I have some questions to try and narrow down your problem. When you say it doesn't shift do you mean the shift lever doesn't move at all or the lever won't shift into any forward or reverse gear with the engine running but will shift into gear with the engine off?
To get your transmission off you will need to remove the driveshaft first before taking out any other bolts to any other components. If you remove the four bolts on each end of the driveshaft flange the shaft should push inward on the splines where the front and rear parts of the shaft slide into each other. If the spline is frozen (rusted) it will require gentle prying and tapping (not beating) with a hammer.
Thats a start... have you ever pulled a transmission before? If not you should try to find someone who has for on site tech support. Some of your parts may not be available and if you break them you could be sitting in the garage a while. You will at least need a floor jack and something to support the transmission and engine before you start. Also make sure the car isn't going to fall on top of you! Use proper jack stands rated for the weight! Disconnect the battery! Do you have an electric O.D. then disconnect all wiring? Did you remove the transmission mount bolts? Remove the clutch linkage? Then remove the bell housing bolts? You may but not sure have to loosen the engine mounting bolts, While supporting engine and transmission at the same time gently wiggle and slide transmission to the rear of the car and out from the engine. Remember children may be present and this may take some time or it may fall apart and crash onto the floor or you. So please be careful!
If I forgot anything which I probably did I'm sure someone will chime in becaus it's late and past my bedtime.

And the sun is finally out, my sons baseball games are over, and you all know what I'll be doing tomorrow.
Harry

GuyShark
06-16-2006, 10:11 PM
It will not shift while the engine is running. In fact, to get it home, I had to turn off the engine, and practically start the car in gear and drive it back to my garage. I could upshift, but forget about downshifting.

The car is up on jack stands, and its by itself in a two car garage. No kids to worry about. I have never worked on a TR6 before. This is my first. I have some experience with Jeeps and Corvettes.

[ QUOTE ]
If you remove the four bolts on each end of the driveshaft flange the shaft should push inward on the splines where the front and rear parts of the shaft slide into each other. If the spline is frozen (rusted) it will require gentle prying and tapping (not beating) with a hammer.

[/ QUOTE ]

Ok, this is what I am experiencing. How far should that shaft push back into the transmission? About how far do I need to pull back the transmission before I can lift it out?

Thanks for your comments! Keep them coming.

TR4nut
06-16-2006, 10:27 PM
GuyShark-

Its been a while since I last did this, but just to clarify: the output shaft does not push back into the transmission - it is fixed. The driveshaft should push back to the rear of the car.

Before you go to this big effort, it might be worth it to check the clutch hydraulics one more time. From your description, the clutch is not disengaging. Also you said fluid level was low - how low? Was there a chance air got into the system from the m/c? Do you see any signs at all of leakage? Either at the m/c or at the slave cylinder?

Anyway, you may ultimately need to pull it as you are doing, but it is a lot easier to work on the hydraulics outside of the trans than pulling everything to get to the inside.

By the way, the trans probably needs to come out 4 inches or so (guesstimate) to get the input shaft to clear the clutch and let you pull the trans out.

Good luck,
Randy.

RomanH
06-17-2006, 12:38 AM
I just replaced my clutch last week. I can not tell you what your problem is but maybe I can help you get the trans out.
You have to disconnect the drive shaft at the back of the transmission at the output flange. Once this is done the drive shaft can be pushed to the rear of the car. You may have to rap the flange with a mallet to break the two parts free. The flange on the drive shaft should go back far enough so that it is even with the drive shaft cover. Do not forget to remove the rear transmission mount. Finally slide the trans back (you will know when it has come out far enough) and maneuver it out the passenger side of the car.
Hope this helps and you get your car back and running soon!
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trboost
06-17-2006, 05:51 AM
HeyGuy,

It doesn't make a differance but is it an OD or 4-sp. The only differance would be the additional wires & weight. There are some bell housing bolts tucked at the bottom, make sure ALL the bolts are out. The transmission supports the engine as well. When you remove all the bolts, clutch linkage & trany mount the dowel pins are now supporting the motor. These may cause the binding along with the hundred year funk. Put a jack under the oil pan using a piece of wood to protect it and gently jack it up to support the engine .
If the driveshaft flange will not seperate use a soft mallet or wood and hammer to persuade it. Take care not to hit it hard enough to do damage. At this point grab the trany and try and rock it side to side or up and down untill it seperates. Take care to reinstall the dowels, they are important.

On installation the jack under the motor will be needed to keep the engine & trany in alignment.

If you have any questions on the fork repair or reinstalling just holler.

Kurtis
06-17-2006, 05:58 AM
GuyShark,

Where in Arkansas are you located?

GuyShark
06-17-2006, 10:04 AM
It is a 4-spd. I did bleed the clutch master & slave cylinder, with no effect. Yes, it does still leak, but I was getting the 5/8" lateral travel out of the pushrod. The failure happpened catastrophically. Shifting fine, then, Nothing. That leads me to belive something broke, and not a gradual problem with the fluid.

I purchased this car from forum member Cain. (he lived in Maumelle, AR). I live in Rogers, AR. The car made the trip home without any problems... then the next day it crapped out.

Thanks for the suggestions, I can't wait to get out in the garage and attempt them.

TR4nut
06-17-2006, 10:19 AM
Sounds very much like you're doing what you need to do, and unfortunately that does mean a trans pull - you've probably already seen it in the manual, but I think my first check would be the release fork cross shaft pin - I'm sure several forum folks will testify as having dealt with that failure point before.

Randy

Popeye
06-17-2006, 03:39 PM
Boy I love this forum... I am trying to get my TR4A tranny out this lovely Saturday!

Does the entire driveshaft / propeller shaft need to be removed, or just the end at the transmission?

After removing the four nut/bolts, should "gentle rapping" cause the front of the propshaft to slide back?

Thanks in advance - and compliemnts on the perfect timing GuyShark!

Kurtis
06-17-2006, 04:01 PM
Hey GuyShark, I know that car. I met Stephen a couple of times down at Ron McLeod's place in Maumelle. If you haven't already done so, you might want to check into the local British car club up there. Here's a link for their website:

https://www.britishironnwa.org/

As has already been mentioned, it sounds like the most likely culprit is a broken clutch fork pin. This is a weak point on all TR transmissions.

Good luck!

TR4nut
06-17-2006, 04:31 PM
Popeye-

I believe you should just unbolt at the trans and you'll be fine, the propshaft should move back enough. The 'gentle rapping really just gets the flanges separated. Once they are separated, the propshaft should move easily. If it doesn't you ought to check your propshaft!

Randy

Popeye
06-17-2006, 05:34 PM
Thanks Randy - I will try more "gentle rapping" and see what happens. (I have undone the propshaft at the rear and front, but it is pretty well frozen in place; rapping at front nor rear seems to separate it from the mating surfaces! 40 years of firm attachment trying to be undone.)

Happy Saturday!

Mike

GuyShark
06-17-2006, 07:30 PM
Its out! I could not get the driveshaft to push back. So, I pushed it down, and was able to lift the transmission over it.

Ok, so now its out, I look, and everything is OK.

Crap. The pins look just fine. I'm going to clean it all up tomorrow and look closer, but a busted pin does not look to be the issue.

Where should I look next?

shorn
06-17-2006, 07:45 PM
I would look into replacing/rebuilding the clutch MC and slave cyl. If one or the other are leaking, there certainly is a problem.

TR4nut
06-17-2006, 08:12 PM
Guyshark-

Just to be sure, by pins are you talking about the ones holding the throwout bearing carrier? If so, those normally aren't the problem and you need to check the other pin that holds the fork to the cross shaft. I think it has a square head.

You've probably done that already, but you said pins, and the bad one is usually just the one I just mentioned. There's a chance you can check it manually by seeing if there is any play between the cross shaft and the fork - there shouldn't be any.

trboost
06-17-2006, 11:02 PM
Guy,

You need to actually remove the Fork Pin. If the symptom matches the cause, the pin will come out missing the tip. The tip breaks off and gets stuck in the fork.
Double check to be sure.

Alan_Myers
06-18-2006, 03:17 PM
[ QUOTE ]
...are you talking about the ones holding the throwout bearing carrier? If so, those normally aren't the problem and you need to check the other pin that holds the fork to the cross shaft....You've probably done that already, but you said pins, and the bad one is usually just the one I just mentioned. There's a chance you can check it manually by seeing if there is any play between the cross shaft and the fork - there shouldn't be any.

[/ QUOTE ]

I most certainly agree that the dreaded taper pin in the fork is the most likely cause of the problem. When it shears off it's usually a ragged break and allows just a smidgen of play, enough to prevent the clutch from releasing properly/fully and yet so little it can be hard to spot without close inspection.

However, the two pins on the ends of the fork, that ride in the TO bearing carrier *do* wear. Over time they tend to flatten on the sides where they rub on the carrier. This adds even more play to the mechanism, also shortening the throw of the TO bearing. These pins are replaceable (or a new fork would come with nice, new ones installed).

The "Scottish" way to fix em is to grip them with a wrench and rotate them 90 degrees, so that an unworn area is now in contact with the TO bearing carrier (Hey, I'm entitled to make the Scottish reference since that's largely my heritage.)

When repairing the dreaded taper pin, you need to drill a hole in the reverse side of the fork, sort of opposite where the taper pin fits in. It's unlikely you can get anything in there to drill an exactly aligned hole, so just do the best you can. The hole is needed to get a punch or something in there to tap out the end of the sheared of taper pin. (Note: If you ever find yourself installing a new clutch release fork, before installation I highly recommend predrilling it with a 1/8" hole to allow removal of the dreaded taper pin, should that ever be necessary.)

There have been a number of discussions here about more permanently fixing the dreaded taper pin problem. These include being sure to get a high quality replacement taper pin, lapping the taper pin into place so that it best fits the cross shaft or making up your own straight-sided pin out of high-quality steel, adding a Grade 8 1/4" pinch bolt off to the other side of the fork (or a roll pin, instead), and even just welding the fork in place.

Search the archives here and also Google around out on the Internet, where you will almost surely find illustrated articles about it. There might be an article in the www.vtr.org (https://www.vtr.org) repair archives or the Buckeye Triumphs website (I haven't looked at either, but wouldn't be surprised if there were articles because this is such a common problem, and was made even worse by vendors supplying poor quality dreaded taper pins a few years ago.) Roger William's "How to Restore Triumph..." books also discuss and illustrate the repair options and methods of reinforcement.

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red_tr250
06-19-2006, 12:58 PM
IMHO, you have the gearbox out...not knowing what you have in there...you may want to consider replacing the PP and driven plate. Rear Main seal...maybe??

Aside from amount of travel in the push rod, there's the cross shaft bushings...easily replaced whilst everything is out & do yourself a favor & drill through the fork & cross shaft & install a grade 8 bolt!

Cheers,

Todd