Help with rotoflex/drive shaft upgrade

[DiscoBlanco]

So I am doing the rear drive shaft upgrade on my 96 disco.

I am having MUCHO trouble getting the centering pin off. It's stucker than shit! I have been hitting it with PBblaster regularly for a week, I tried propane heat, and a special puller tool that a friend made.

THe tool is a piece of pipe with a steel cross bar and an 8mm bolt. THe bolts strip out and the centering pin has been stripped and re-threaded too many times.

I have an aceteleyne torch that I have been using to heat it, but I am afraid to get too agressive with it in fear of damaging the diff.

I started trying to cut the flange off with a cut off wheel.... I have been at it for an hour, gone through 3 wheels and made a bunch of sparks.... But not much progress.

Any ideas????

 

[p m]

It is a royal bitch. Blue will tell you all about it.
My trick was to never replace the center bearing while replacing rotoflex; after four replacements, the thing practically fell out when I converted to U-jointed driveshaft.

Speaking of the heat - you'll have to heat the peg red-hot before you do any damage to the diff.

 

[p m]

Now you got me thinking - what I'd do now is to measure the O.D. of the peg, and cut the outside thread on it, about an inch long. You could then use a big nut and spacer to pull it out, instead of puny 8mm thread inside it.

 

[fishEH]

Sounds like you owe me a bolt! :rofl:

 

[Jake1996D1]

Stop being scared of heat....

If you're that worried about it change the gear oil when you're done

 

[DiscoBlanco]

I was more worried about setting it on fire or tempering the bearings...

At any rate, I started hacking away at it with a portable band saw.... Not much room to maneuver down there, but I cut enough of it off enough to get the plug out in pieces.

what a fucking turd of a job....

 

[pdxrovermech]

sounds like a a few new rotoflex joints over the next 20 years is a better idea.

 

[Blue]

I was more worried about setting it on fire or tempering the bearings...

At any rate, I started hacking away at it with a portable band saw.... Not much room to maneuver down there, but I cut enough of it off enough to get the plug out in pieces.

what a fucking turd of a job....

And another rotoxflex to ujoint veteran is born. Good job.

 

[DiscoBlanco]

Sounds like you owe me a bolt! :rofl:

Dude, the bold you gave me was some other imperial size... :thehand: I did buy a few extras though.

 

[fishEH]

Dude, the bold you gave me was some other imperial size... :thehand: I did buy a few extras though.

HAHA! I think that's the one that I used, no clue though.
Did you get it done?

 

[DiscoBlanco]

Almost. The pinion bearing was toast. I just got the new one in the mail yesterday. All that remains is getting that second half of the drive shaft together. I will let you know how that and the bushings are working tomorrow.

I think the steering rods and ends are next... All of the ball ends seem pretty tight, but the boots are in pretty bad shape.

 

[Jake1996D1]

So now you have to remove the diff to change the pinion bearing? That sucks

 

[fishEH]

Almost. The pinion bearing was toast. I just got the new one in the mail yesterday. All that remains is getting that second half of the drive shaft together. I will let you know how that and the bushings are working tomorrow.

I think the steering rods and ends are next... All of the ball ends seem pretty tight, but the boots are in pretty bad shape.

What second half of the driveshaft are you talking about? Ar eyou putting new ujoints in or are you referring to the four bolt flange on the diff?

 

[DiscoBlanco]

Just the diff side. The other side is hooked up so its just hanging there like a flaccid.......

I wont have to pull the diff for the bearing. The forward bearing comes right off the pinion. It turns out the bearing that I had was not all that bad anyway.... I thought it was toast because there was a lot of play in it. It turns out that the new one is the same way. Oh well. 20 bucks is 20 bucks. The Disco has 160k miles on it, I had it apart, its getting a new oil seal. I'll call it cheap insurance and hope that I never have to touch it again.

 

[Jake1996D1]

Just the diff side. The other side is hooked up so its just hanging there like a flaccid.......

I wont have to pull the diff for the bearing. The forward bearing comes right off the pinion. It turns out the bearing that I had was not all that bad anyway.... I thought it was toast because there was a lot of play in it. It turns out that the new one is the same way. Oh well. 20 bucks is 20 bucks. The Disco has 160k miles on it, I had it apart, its getting a new oil seal. I'll call it cheap insurance and hope that I never have to touch it again.

Dude... You can't just change a pinion bearing without resetting the preload.. That's probably your issue and your inner bearing is probably in bad shape as well.... In short your diff has play in it
because it doesn't have enough preload.. Did you change the old race out????? I see bad things in your future...

 

[DiscoBlanco]

DUDE

.... I thought it was toast because there was a lot of play in it. It turns out that the new one is the same way.

Note, there is nothing wrong the the bearing. The bearing has play, not the diff.

 

[Jake1996D1]

You obviously know nothing about differentials... It's cool do what you will, I was just trying to help you out

 

[fishEH]

You obviously know nothing about differentials... It's cool do what you will, I was just trying to help you out

What's the proper way of replacing these bearings? I'll likely have to do mine soon anyways.

 

[Jake1996D1]

It's in the rave manual. I'm done trying to help people. Fuck you all!

 

[DiscoBlanco]

What's the proper way of replacing these bearings? I'll likely have to do mine soon anyways.

Let's hear it. Then we'll all know....

Anyway Brett, Page 480-486 in the RAVE if you want to open the diff and replace the inner and outer bearings which is what I think Jake is under the ASS-umption that I have done. Then you have to mess around with shims and pre-load.

I only messed with the outer bearing because when I looked inside, there was an O-ring hanging on the pinion shaft. I pulled it out and noticed the bearing would be easy to come out. I pulled that and I noticed the play in the bearing. At first I thought the O-ring was from part of the bearing, but after I confirmed with the bearing house that all of these bearings have a bit of play, I later realized that the O-ring came from my oil seal....

Sooooo.... since I have not messed with the inner bearing and shims, all should be good to put back together. The original bearing is probably in decent enough shape to just put it back in.