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No question here - just thought you guys might be interested in the pic.



With the addition of the ratchet strap, the Harbor Freight transmission jack works pretty well.

Now to figure out why it whirrs with the clutch out in neutral.

Prolly the input bearing. Does the noise gradually stop when the clutch is depressed and the shaft comes to a stop?

Yes. Main input bearing looks ok though - I have not yet removed it from the case. The only things spinning in neutral are the input shaft and cluster gear, so it has to be there.

Or TO bearing riding against/on the clutch?

Seems unlikely. There's no unusual wear on the cover fingers or the TO bearing. There was free play in the pedal before I took it apart.

When I got the truck, two of the bell to adapter bolts were loose by about 1/4" and there was a gap on one side. The rubber trans mount is in two pieces. Tightening the bolts did not change the noise. I suspect that misalignment of the input with the crank caused excess wear of the main input bearing and that's what's noisy.

tgreese wrote:Seems unlikely. There's no unusual wear on the cover fingers or the TO bearing. There was free play in the pedal before I took it apart.

When I got the truck, two of the bell to adapter bolts were loose by about 1/4" and there was a gap on one side. The rubber trans mount is in two pieces. Tightening the bolts did not change the noise. I suspect that misalignment of the input with the crank caused excess wear of the main input bearing and that's what's noisy.

I think you're on the right track. When I did mine, the clutch seemed like it was dragging but it was the input shaft being spun by the pilot bushing in the crank. Such a small thing, but such a pain to get to!

I'd say pocket roller bearings between the input and main shafts. Very common failure on T-18s.
One hint of this is the shifter moving fore and aft when accelerating/decelerating.

Tatsadasayago wrote: I'd say pocket roller bearings between the input and main shafts. Very common failure on T-18s.

That makes sense - thanks.

One hint of this is the shifter moving fore and aft when accelerating/decelerating.

Is there a way to test that on the bench, or would it be obvious when I pull the input out and look at the bearings? I would measure the bearings...

If the rollers are rough/bad, you should feel them grind while pushing the input to the rear and turning while holding the mainshaft. Often the input bearing will get eaten up by the thrust allowing the input to move toward the main shaft causing metal shavings to further eat up the rollers.
Pulling the input is obviously the best way to verify this.
If the rollers are bad but the input bearing surface isn't, Inland Truck Parts has the rollers as part of their rebuild kits.
[EDIT] A trick to saving a beat-up input shaft was to have the inner race turned on a lathe and getting over-sized rollers. I'd have to call my Dad to see if he remembers the application for these.

So Crown sells the pocket bearing roller by itself, easy-to-remember Jeep PN 912345. http://www.morris4x4center.com/crown-ro ... 12345.html No time to look at this more during the week - I pulled the trans Sunday afternoon and was pooped, so I did not do much more other than remove the adapters and bearing retainer. I guess I'm not a 20 yo anymore I must have gotten up and down from the garage floor 100 times.

Standing by for advice on machining the input shaft, if needed... pending results of inspection.

Awaiting parts and a meter stick of M16x1.5 all-thread to extend my puller.



Two pieces of EMT over the pliers handles make lock ring removal much easier.

My buddy Tom is making a trip to Connecticut and he could bring you a rebuilt T18 I've got laying around for real cheap.

Thanks for the offer, but I'm sure I will use the transmission I've got now. Plus, it would have to be a T-18 from a '80-86 J20 to be useful.

I sent you an email ... did you see it?

Found and replied.

If Tim's not interested in it, how cheap are you thinking for that T18? I could really use it.

PM me, we'll work something out.

Ok, so I used my improvised puller to remove the bearings - worked great.



Was cheaper than a commercial puller, but still not free. The threaded rod was about $30 from mcMaster-Carr, and I used the Harbor Freight "Large Bearing Separator."

The front main bearing is the culprit. Maybe you can see the pitting on the inner race.



Hard to get a good shot of this, but if you look at the inner race, there is significant pitting. Clean the oil out of the bearing, and you can feel the roughness.

The input shaft pocket, pocket bearings and output bearing are perfect, so I'm done with disassembly.

That's KILLER good news!

Tatsadasayago wrote:That's KILLER good news!

Sweet, that was easy.