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Dropping gearbox to replace fork pin, need guide

Steve1970

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my clutch fork pin appears to be toast.. got the car jacked up in the rear and the clutch appears permanently engaged, even with the slave detached from the lever and with me manually actuating the fork lever.

soooo good times ahead... i've got to drop the tranny, and i will probably replace the clutch, release bearing, etc. while in there as well. all stuff that i've NEVER attempted to do before.

i don't like the haynes manual procedure for this, the pictures aren't even from a tr6. can someone recommend a good guide (book, online, or cd) that i can purchase that details clutch replacement procedure, with good details on how to drop the gearbox (j type od), with good pictures?

many thanks!
 
Can't recommend an online guide, but I can warn you that you need to have a jack underneath it when you pull it. An o'd tranny is about 100lbs all up iirc, and you don't want it swinging on the input shaft.

Two people to reinstall - one to lift, one to shove bolts in place also make the job a lot easier.

Oh and whatever else you do, don't forget the dowels...
 
never pulled my trans but arent you suppose to remove passenger seat, carpet, tunnel and pull it thru the interior and out the passenger door? That way you could make a sling and use a lift or rafter and pulleys and ease it out,


Hondo
 
Re: Dropping gearbox to replace fork pin, need gu

And also don't forget to support the rear of the engine, otherwise it will come down at the rear as you remove the trans and you will be replacing all kind of expensive items, like a radiator, engine mounts,etc. The engine mounts in a TR are way forward of the CG, the trans mount is what supports the rear of the engine assembly. :wall:
 
Re: Dropping gearbox to replace fork pin, need gu

Steve!

As everyone on the Triumph forum can attest, Tinster
knows very little of things auto mechanical. But
I did stay at a Holliday Inn and I did manage to pull
my tranny out to replace the failed clutch taper pin.

1. Put your car on 4 jack stands
2. Remove the 4 wheels
3. Remove both seats and seat rails
4. Remove the steering wheel
5. Remove the carpet
6. Remove the emerg brake tunnel cover
7. Remove the tranny tunnel cover
8. Get a 24" ratchet extension
9. Put 2X4 blocking tight under the engine
10. Get a buddy
11. Unbolt the tranny mount bolts
12. Remove the starter
13. Start removing the 16 tranny/engine bolts
14. Lift the tranny up and over the passenger door.

Maybe you can figure how to remove it from underneath.
I was unable to do so. With all the work involved, you
should replace the entire clutch assembly. IMHO.

PS: It took me 8 hours to get the actual clutch out.

dalepit.jpg


tinster

<span style="color: #990000">Edit: Maybe ya can do it with the steering wheel in place !! :lol: </span>
 
Re: Dropping gearbox to replace fork pin, need gu

hondo402000 said:
never pulled my trans but arent you suppose to remove passenger seat, carpet, tunnel and pull it thru the interior and out the passenger door? That way you could make a sling and use a lift or rafter and pulleys and ease it out,


Hondo

The problem with this is that it has to go a LONG way forward - we thought about using an engine crane, but the dash got in the way. A trolley jack (on wheels) made moving it into place a lot simpler.

iirc it's a lot easier to get in if you let the back of the engine drop down just a little bit. That in turn makes putting the gbox mount in place a little more like exercise than I would have liked though.
 
Re: Dropping gearbox to replace fork pin, need gu

I didn't pull the wheels, steering wheel, Try the Bently manual. I did mine by myself, if you didn't have to pull the interior, it would be a piece of cake. Mine is OD.. Put a thick blanket on the passenger floorboard so you don't destroy it. The real problem is what clutch to put back in, cause unless you can find a NOS, they all got issues. If you don't know it, the reason the pin failed, is because of excessive pedal pressure due to junk pressure plates. If my pin failed, I would check my crankshaft end play, because the reason the crankshaft thrush bearings fail is the same.......Due to the difficulty in removing the interior, mite not be a bad time to rebuild the trans, or install OD if you don't have it. Have a fun summer! PS, get you wallet out, you will need it. However, after re reading your post, sounds more like a pressure plate problem to me. Has the car been sitting for a long period of time, if so the disc may be stuck to the flywheel. Oh, and before you start this job, unhook the battery............
 
Re: Dropping gearbox to replace fork pin, need gu

wow, thanks for the info guys. i'll pick up a bentley manual, and an extra floor jack to support the engine.

i'm sure i'll have questions later on, especially when it comes to deciding which clutch to purchase.

it all seems so overwhelming right now... i'll start ripping out the seats tomorrow
 
Re: Dropping gearbox to replace fork pin, need gu

Before you do this, have you tried (carefully!) to unstick the clutch disk as a possibility? What searcherman said does happen quite often if the car has been sitting.

Easier than a trans pull - put the car in gear, push in the clutch, and try to start the car. If its just stuck this will probably unstick it. Of course do the safety thing, nothing around the car, brakes firmly on, etc. to avoid a bigger problem..

Randy
 
Hey Steve,...I'm "ever the contrarian",...but after trying to "bench press" a TR4 OD Transmission, I swore I'd NEVER do it again.
Whenever clutch issues raise their ugly heads, I remove the engine AND Transmission. I takes an extra couple of hours on both ends, but you don't have to be nearly as strong. Engine hoists in my area run about 31 bucks, and I normally plan for two days...you can clean the engine room...paint the engine, and not break your back trying to straddle a wayward transmission while trying to align the input shaft.
The advice earlier about supporting the rear of the engine is pretty important because it aids alignment.
Just a thought,...
Good luck, Bob
 
Randy, i'm 99% sure the disk isn't stuck because (1) i drive it every 2 weeks or so and there were no signs of a stuck disk last time i had it out, and (2) the disengagement failure was a gradual failure that i had been able to work around by moving the slave cyl rod up a notch on the fork lever, replacing the pedal box bushings, bleeding the hydraulics, etc. i think the fork just eventually became so twisted that the pin just gave way.

but what the heck! i will gladly try the ol' start in gear w/ the clutch depressed trick tonite for good measure.

Bob, i'm giving the engine+tranny removal some serious thought, like you say.. it would be a good chance to paint the engine bay. i'm assuming the engine+tranny would come out together (attached). space is extremely limited in the garage though but i think i could pull it off.
 
Hey Steve,...One of the issues is how tall your garage is,... I've always had to remove the engine outside, and roll the engine and hoist under cover. A TR6 engine and transmission are pretty long and require a higher lift than you might think.
Once it's clear of the car, of course you can move the TR pretty easily.
Using the "Sands" method of Project timing, If you think it will take 3 hours to clean and paint the engine bay...multiply that estimate by 4.
Good luck Bob
 
Re: Dropping gearbox to replace fork pin, need gu

Two ways, both have pluses and minuses. Removing the engine/tranny does indeed allow you access to the engine bay but does require removing the bonnet, which can be a real pain to re-install correctly. Plus, pretty much everything needs to come out - cross brace, radiator, etc. It can be done easily with an 8' ceiling. I found that removing the front wheels and lowering the front of the car till the front end almost touches and at the same time raising the rear quite high will lessen the stab angle of the unit coming out/going in. You will need an adjustable hoist that allows for pretty extreme tilt of the engine. And it has to be on wheels to maneuver to and fro. Don't even think about pulling off a ceiling joist. I have built a throwaway rectangular frame out of 4"x4" timber (two high) that fits the bottom of the block (sans oil pan and oil pump) that allow me to rest the whole thing on after getting it out. That way you are floor-level and can easily unbolt the tranny and slide it backward. You won't need an engine stand either. Easier to stab the tranny back when you are ready to bolt it back up.
The other option (removing the tranny only) only requires removing the interior (not the steering wheel) but you must brace the engine from the back. A scissor jack or floor ☼☼☼☼☼☼☼☼ the oil pan (with thick rags in between) will give the slight adjustability you will need. A beveled piece of 2"x4", jambed in between the rear engine plate and the block will hold suspend the engine safely will working on the tranny. The real downside to this approach is you need a really strong back and preferably a helper (2 helpers, because the first one won't come back after the first session. In fact, you may never see him again for a year) because this thing is heavy and you have to maneuver a bit to get the TO bearing to stay in when reinstalling. I have done both ways. The engine out is physically easier and a lot more exciting, the tranny only will make you call the chiropractor.
 
Re: Dropping gearbox to replace fork pin, need gu

TR6BILL said:
..., the tranny only will make you call the chiropractor.

bill, with the interior removed from the interior compartment, aren't we just talking about manually pulling up the tranny enough to clear the floor and then just swinging it 90 degrees and allow it to rest on the interior compartment floor? i'm assuming this would leave me with enough space to do the fork pin, bearing jobs.
 
Re: Dropping gearbox to replace fork pin, need gu

It's not a straight lift - you have to pull it back then up.

Getting it out isn't the problem - it's putting it back in again that is tough. I'm not a small guy by any means, and I found it to be hard work.

That's why I suggested the jack to rest it on while you manoeuvre it.
 
Re: Dropping gearbox to replace fork pin, need gu

Hey Steve,...If you remove the transmission, the issues are:...keeping the engine at the same angle, so the input shaft doesn't bind when you put it back together. You'll be at an awkward angle to pick up anything heavy and the firewall transmission tunnel lip can be problematic, as well.
Mark the bonnet hinges with a dab of paint, on at least two sides and it will help line it up when you reassemble,..if you go in that direction.
Keep in touch...let us know how things progress.
Good luck Bob
 
Re: Dropping gearbox to replace fork pin, need gu

alana said:
Getting it out isn't the problem - it's putting it back in again that is tough. I'm not a small guy by any means, and I found it to be hard work.

That's why I suggested the jack to rest it on while you manoeuvre it.

for reinstallation of the tranny i was thinking of using two jacks. one at the prop shaft end and the other under the drain plug. that way i could half@ss tilt it up/down when i go to line up the bellhousing/engine.
 
Re: Dropping gearbox to replace fork pin, need gu

alana said:
It's not a straight lift - you have to pull it back then up.

Getting it out isn't the problem - it's putting it back in again that is tough. I'm not a small guy by any means, and I found it to be hard work.

That's why I suggested the jack to rest it on while you manoeuvre it.

<span style="color: #990000">Alan,

So right you are. David and I also installed a temporary 1/4 " bolt
(loose) at the engine top to serve as an initial guide and hanger
for the tranny until we got the alignment onto the dowels.

Steve, you really don't want to attemp any of this clutch work with
the tranny sitting sideways in the cockpit.

1. You will be amazed what a slimey, G-awful
mess the tranny is once you pull the cover off.

2. Odds are high you have a rear shaft and front plate oil leak
you will want to correct. REAL difficult with tranny inside the cockpit.

3. You probably should change the tranny oil. Kinda difficult and messy
with the tranny sitting inside the cockpit

4.You probably should inspect (minimum) your flywheel. If available, get it resurfaced.

5. All this time you've already spent?? Spend the few extra $$$ and install new clutch
plates! I also had but a sheared off pin and oil leaks. I replaced the entire clutch
assembly and I am happy I did.

If you do nothing anyone here recommends- do the fork shaft reinforcement.

Keep us informed

The non-auto mechanic guy
Tinster
</span>



clutchbarmods.jpg



cshaftcover.jpg



tobearing2.jpg
 
Re: Dropping gearbox to replace fork pin, need gu

I haven't had to replace the tapered pin yet, And I do see the advantage of thru bolting the fork, but what is the 1/8" access hole for?
Dale has the "#1" indicating the hole in the first picture.
Thanks.
 
Re: Dropping gearbox to replace fork pin, need gu

poolboy said:
I haven't had to replace the tapered pin yet, And I do see the advantage of thru bolting the fork, but what is the 1/8" access hole for?
Driving out the remains of the broken pin.

For years and years I thought the same thing "I've never had a problem, so why fix it ?". Then I had a taper pin break, and my thinking changed to "Why the #@! didn't I fix it when I had the chance !"
 
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