Rebuilt T-14 Won't spin in nuetral

I need some help. I'm starting to think I've lost all mechanical ability.....

I'm trying to reassemble my T-14 (doing a rebuild), and I've basically got the tranny back together except for the shift tower.

Here's my problem. With the trans in nuetral, I can spin the input and output shaft in separate directions (or hold one and spin the other) for a few revolutions until it locks up and I can't turn them anymore.

As I am turning the shafts, I notice the space between the input shaft and the front sycro gets larger then smaller. It's when the space gets closest the shafts lock up. After they lock up, you can turn the shafts back in the opposite direction and watch the space get bigger, then smaller, then lock back up.

I need some help on this one. I've been jeepless for over two years. I need my jeep back on the road. Help!

Jon

 

Sounds more like you either got some junk in the needle bearings or maybe one of them is out of position between the input shaft and the main shaft...


BUBBA

 

I agree with what Bubba says, it sounds like a needle bearing problem, you may want to make sure one of the needles is not missing, if so they will roll at an angle and force the shafts to move toward or away from each other while turning and eventually lock up like a sprag clutch.

 

yeah what bubba said. if you pull the rear gear the needle bearings will come out and jam up in there. i say that because i had that happen to me when i split the transfercase and tranny and tried to put together after i pulled the rear gear and when i did i guess the needle bearings went all goofy.

 

Before you disassemble anything, you might try putting the shift tower back on and see if it still locks up. Without the forks holding the gears in thier respective positions they may partially engage and cause lockup. If it still locks then I'd have to agree with the other people that it may be a roller out of place.

 

Jeepenstein wins the prize. I'm able to see the needle bearings through the oil slot in the input shaft, and I see that my needle bearings are shifting. When they get too ****eyed, the shafts lock up. Guess I've either got too much wear in my input shaft, main shaft, or the needle bearings (which I got in a rebuild kit) are not right. I've mixed & matched parts between old trannies, and I knew something like this would happen....

Thanks,

Jon

 

the T14 should have 21 pilot rollers total
FYI

 

i'd be interested in the needle bearings you were using... i rebuilt mine roughly three to four times with new bearings only to get about 50 miles on it before things would explode very loudly and the jeep went into "limp mode".

 

YAAAAAY! What's the prize?

BUBBA

 

Bubba,

Bag full of used T-14 parts? That's about all I can afford right now....

Also, does anyone know the correct measurements for the following parts?

- Inside Diameter of the input shaft bearing surface
- Outside Diameter of the main shaft bearing surface
- Outside Diameter of the needle bearings.

I've got two different input shafts and main shafts from two different T-14s, and they all seem to measure pretty close. I don't seem how these trannies were still operating without completely grinding the needle bearings to dust before I took them apart..

Jon

 

It isn't rocket science, but the clearances have to be at least close. I have a complete basket case T-14 out there, almost everything is shot. Plus it was gonna cost a bunch for the parts to fix it. So I ended up with the T-90 back in there.

-Hill

 

Thanks for the helpful info Fithian62, but what I need are some real measurements so I can tell which part (if not all) are worn and need replacement. There is no "obvious" signs of wear on either of the shaft areas, and if one is out of tolerance, and the other is OK, I don't want to buy more parts than I need.

Anybody have any idea? Anyone have some "new" parts they could measure?

Thanks,

Jon

 

HAha, thanks but I have two bags of T-14 parts already.. unfortunatley I cna't measure any of them (see avatar)..


BUBBA

 

Anybody have a source for this info? I've emailed Herm since I got the rebuild kit from him, but haven't gotten a response yet.

PLEEEESE???

Jon

 

Yeah, when I installed the needles in the main shaft, there was a small "gap" between the first and last one (around 1/4-1/5 the size of a needle). And I had them held in place with assembly grease.

The needle bearings were not the original problem. They actually looked OK when I took them out. The reason I had to rebuild was the rear main bearing basically fell apart (ball bearings fell out in to the Xfer case).

The odd thing is the fit is the same between 2 different input shafts (one's my original, one is from a donor tranny). They didn't bind up when in nuetral before the rear bearings exploded.

Keep the advice coming....

 

Did you count the needle bearings to make sure you had the right number of them? There should be NO space left between the bearings when they are in place. I'd guess you had space for one more in there.

 

Nope. 21 bearings. Ther was a slight gap left with all of the rollers in, but not enough for another bearing. I would say its about 1/5 the size of a bearing. Would that be enough of a gap to cause a problem? Odd thing is, both input shafts I have (both used) have the same gap with the rollers in there. And neither shaft (input or main) show sign of wear on the bearing surfaces.

Herm's offered to call me this weekend (I've basically barraged him with emails), so hopefully I can get some answers soon.

Thanks,

Jon