Gearbox challenge - I am beaten

[plc]

G'day All,

I have been AWOL for quite a while. Between, work and the two boys (Charles now 8 months) I occasionally lurk on the forum but rarely post. The mighty LS has been a trooper and rose to the challenge when we became a one car family for a while. Alas after many commutes it became stuck in second gear. Being an ever considerate bike it failed just as I rode into my school's driveway. Being an Industrial arts teacher (sort of like a shop teacher to those in the US) this is not bad as I can use all the facilities at work. So I had the gearbox out in 2 and 3/4 hours, my best yet.

I made a tool to hold the output flange while I undid the 220 Nm nut. I thought this was a big achievement. But when I made my first puller I simply bent the steel bar I made it from. I had bought two M8x1 bolts and an M12 bolt and nut to act as the puller on the output shaft centre bolt with the 6 mm steel bar joining them. So when it bent it I thought, fine I will use thicker steel. So this time I made a puller from 12.5 mm thick steel bar.

This time the bar didn't bend, but the flange still didn't release. Instead I sheared the M12 hi-tensile steel bolt off as I tried to get the flange off. So even though I was determined to fix the gearbox its innards remain a mystery to me. So off it went to the shop.

Next time I will have the Cycleworks puller and I will finally get into the box. Hopefully I won't need to use it for a long time.

Am I the only one to find the flange impossible to remove?

Best to all,
Paul

[Lucky_Lou]

See topic R65 problem with gears and JustinB,s last post you have to heat the flange to remove it (im asuming its the same one) as this job repair job has been quoted at 3 hours it may be better to take the bike to South Africa   [smiley=thumbsup.gif]
Lou

[plc]

I tried both boiling water and a "gentle" use of the oxy torch. Heat made no difference sadly.

Paul

[Barry]

Sheared an M12 Hi tensile bolt !

Must have been tight.  

Smacked it with a hammer while under tension ?

[plc]

Hi Barry,

Yes I hit it so many times when under tension. I had a mate with lots of vintage bikes helping me and he was shocked it didn't come away. After trying hitting it under tension with heat the look he gave me told me what I knew; it had to go to a specialist.

Paul

[nhmaf]

They do go on there TIGHT - when they do release it often makes a very loud "crack", but I've only experienced helping someone with (1) of these, and it came off more easily than it appears yours will.
Hmmm

[Bob_Roller]

Not that it would help in this situation, but working on aircraft for the last 34 years, when we get in a situation like yours, a good swift hit with a 9X air hammer helps out in a lot of instances .

We use rivet sets for button head and countersunk rivets .

[tvrla]

The first one I removed was my 76 R90, and it didn't come off easy. And, of course, I didn't have all the proper tools either. I made a puller out of a piece of 1/2" steel with a hole in the middle. With that bolted to the flange, I was able to use a gear puller to apply pressure to the output shaft.

I'd turn it a half turn and then tap on the shaft - with it pointing away from me, of course!

I got to a point where I couldn't turn the puller any more, so had to release the pressure and grease the shaft.

The second time around, after many half turns and tapping, with a loud CRACKKKKKK the output flange with puller sailed across the room. Was I ever happy it was pointing away from me!

I discovered later that at some point it must have run loose because both the flange and taper were scored, providing more bite than usual.

I've done ten or fifteen transmissionss, and never once needed to heat the output flange to remove it. The cover, however, needs quite a bit of heat to come off.

[Justin B.]

I made a simple puller and used an air-impact wrench and it popped right off.  Heat is required to remove the rear cover...

[plc]

That's what I should have made Justin. Did you use a mill for the centre hole or a lathe with a  4 jaw chuck?

Paul

[Justin B.]

Paul,

I used the mill for the plate and turned out the threaded part in the lathe.

It's very rigid, I don't think it would work very good with any springiness, and the air impact wrench imparts plenty of "shock" to go along with the torque...