What’s Wrong with my Transmission...and Other Stuff

During my mis-spent youth working on cars, I once installed a low/reverse shift fork in backwards. It just plugged it a boss on the rail and would spin in circles, but it had a slight offset to it.It looked right and went right together. In the mid 60's there was no U-Tube videos or internet downloadable parts books, and of course I was a broke dumb kid and too cheap to by the factory manual. Needless to say, the first shift from reverse to low; the tranny went into low and reverse at the same time. My first experience with an IED (Improvised Explosive Device).!!!!
 
Stakebed said:
Carter, you would be referring to the heim linkage between the cross shaft and the throwout bearing arm? That stock linkage is adjustable. If you want to replicate that length, which length would you choose? If, on the other hand, you are referring to the link between the pedal arm and the cross shaft, that link length is fixed. As I've stated, I'm a bit concerned if this linkage is the cause of your issue since I followed the lead. The main difference between our mods is that I used a male and female rod end for the upper linkage.
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I want to replicate the length of the fixed rod between the clutch pedal and the cross shaft.
 
Hang in there Carter, you have a good understanding of all the components working relationships and will no doubt resolve the problem!
 
Lookout Ranch said:
I’ve been going around and around in my head trying to think of a problem that explains symptoms. So far I’m stumped.

Here’s an example of how weird it is. We were at a stop sign getting ready to pull onto the highway. It’s in first gear and the clutch is in while I wait for an opening. I let the clutch out a little to go, then decide to wait for a better opening and press the clutch back in, but power continues to be transmitted to the wheels.

I can’t take it out of neutral, so I turn off the key, take it out of gear, put it back in first, put the clutch in and restart and it’s fine, no power going to the wheels and I can move the shifter freely in and out of first.
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Sounds like a clutch release issue to me ! The pressure on the shifter goes away when you shut the engine off means you took the drag off the clutch disc ! That needs to be completely free when you press the clutch pedal. 34 years in the Transmission business tells me to go over linkage really good and a peek at motor mounts and movement might not hurt. Then if all looks good.....get that clutch out of there for a good look.
 
Maybe you could give this a try. Jack the Willys up, put jack stands under the axle, make sure you're in 2wd. Have someone start the Jeep with the clutch in while you watch and see what happens. Do the tires turn, is anything binding, strange noises, anything smell funny? Pull the inspection plate and watch the clutch go on and out with the engine running. There are a lot of fairly easy ways to check things out.

If that doesn't work it may be time to take it apart and check the internals out.
 
The hard part is getting the transmission and transfercase in and out of the wagon. The rebuild on a T90 isn't bad at all. As far as you go in your wagon, might be worth it to pull all that apart?
 
You're probably going in the right direction looking at linkage, but here's something that happened to me awhile back and it might apply. I don't know anything about clutches, so you might be better off ignoring my post. On my clutch, there are four good-sized springs that--to someone who doesn't know how a clutch works--look like they don't do anything. One of those springs fell out and turned sideways, so the clutch was sometimes jammed and seemed to be engaged. Before I dealt with the problem, I heard the spring rattle around and fall completely out, and the clutch worked great for awhile. Then another spring did the same thing. When I got up the guts to take the clutch disc out, it was missing two springs. If it makes a difference, I have a two-wheel-drive F4-134.
 
Your symptoms sound similar to what I encountered years ago on my wagon. The clutch linkage has a cross shaft between the frame and transfer case, IIRC. This cross shaft is hollow and rides on ball fittings at each end. One of these ball fittings had partially unthreaded. I think it was the one inside the frame rail. With normal flexing between the drivetrain and frame, this ball fitting could flop around a little bit and didn't always land in the same spot. Sometimes the clutch action was fine, other times it wouldn't release, or just barely so.

If you crawl underneath to check the linkage, there's enough spring tension on the cross shaft so it doesn't seem loose. The only way I found it was while preparing to remove the transmission to replace the clutch. I went to remove the cross shaft and the one end fell loose. It's very simple to check before digging too deeply elsewhere.

Hope this helps,

Karl


Clutch pivot.jpg
 
I also think it is a clutch problem. It gets stuck in gear when torque is applied, that you cannot release with the clutch pedal. One more possible cause is if the input shaft is seizing in the pilot bearing, that will give these symptoms. Or as mentioned pieces of lining that came loose sounds fairly likely even if the disk is new. Also I once had a disk spring hub come partially apart, a couple of blocks from home. I was at a stop sign, and before I had a chance to engage the clutch it took hold and started moving. I went straight home skipping a couple of stops and took it apart. It was a VW but any clutch could do this.
 
martisan said:
I also think it is a clutch problem. It gets stuck in gear when torque is applied, that you cannot release with the clutch pedal. One more possible cause is if the input shaft is seizing in the pilot bearing, that will give these symptoms. Or as mentioned pieces of lining that came loose sounds fairly likely even if the disk is new. Also I once had a disk spring hub come partially apart, a couple of blocks from home. I was at a stop sign, and before I had a chance to engage the clutch it took hold and started moving. I went straight home skipping a couple of stops and took it apart. It was a VW but any clutch could do this.
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I had a John Deere 350 crawler with an automatic reverser stuck in forward and reverse at the same time. one of the clutch disc (multiple disc like an automatic transmission clutch pack) broke in half and jammed one half between two others causing it to not disengage. Flat killed the engine when trying to go into reverse.
 
Big Dog Frank said:
This is what I used. It was a pain getting it up in there but it has worked for a couple of years now. Sorry no part numbers or supply source. They were in a junk drawer in the shop.View attachment 76611
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Can someone tell me what the OEM length is on this clutch linkage rod? A simple end-to-end measurement would be fine. Thanks!

I put my old pieces someplace "safe" and now can't find them. :(

Edit: Thanks, but I no longer need this! I found another old worn one I'd squirreled away.

Edit 2: For the record, the old clutch linkage rod length is 3-15/16" end to end, outside measurement. This is an old one, looks well made, possibly OEM. Center to center looks like 3-19/32". Bear in mind, this is an old one, so it may have stretched slightly over the years.
 
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A brief update.

I had a chance to spend some more time with it, and still no joy.

The clutch still disengages properly when the pedal is depressed on one occasion, then doesn’t the next.

What I’ve done so far:
— Replicated the proper fixed length of the clutch pedal linkage rod and carefully observed the movements of the Heim joint linkage elements when the clutch is depressed. The linkage appears to have little or no excess play or flexing.

— Examined and observed other parts of the clutch levers, pivots, etc. to be sure they anren’t loose, worn or flexing. The pivot balls on the frame and transmission are both relatively new and tight, as is the cross shaft.

— Checked motor and transmission mounts to the sure they are secure and uncompromised.

— Tightened all transmounting and linkage-related nuts and bolts.


Other observations:

— The eye for the linkage on the lever that pivots the t/o bearing shaft is somewhat worn from years of wear, but that can be compensated somewhat by linkage adjustment and doesn’t seem related to the current problem. The Heim joints actually seem to help with this malady because the through-bolt can be tightened so that it doesn’t cant or twist in the eye when force is applied.

— When the engine is running, the flywheel and crankshaft move fore and aft a surprising distance when the clutch is depressed and released. I’m wondering how much is normal and if I need to drop the oil pan and crankshaft and install a new rear main bearing. Is there another retainer that would control this movement? (It’s a shame to open it up because it runs so well and leaks almost no oil from the main seals.)

— This has the larger “Tornado” clutch and pressure plate that Walck’s offers as a substitute for the regular ones that aren’t available anymore, or weren’t at that time. (The step on the flywheel is machined off accordingly.) I’m wondering if this pressure plate has harder springs and requires greater force to operate, creating more strain on the entire clutch system.

— It occurs to me that I still need to check the tightness of the wired keeper bolt that secures the t/o bearing to its pivot shaft. I’ve observed the movement of the t/o bearing with the clutch cover off but haven’t specifically checked this connection.


Anyway, it’s an interesting puzzle. Just for confirmation, I’m going to reinstall stock linkage and see if it makes any difference. Based on what I’ve seen so far, I don’t think the Heim joints are the issue
 
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On most engines that I've worked on, crankshaft endplay is only a few thousands of an inch. If you can literally see the flywheel and crank moving fore and aft, that might be your problem. Just guessing but perhaps the thrust flange on one of your main bearings is worn. Hopefully Carter, one of the members that has rebuilt your engine family will chime in.
 
OK, so I found at least part of my problem.
Input shaft end play. The retaining ring on the front must have failed or be missing. Hmmmmm.
A56FC88E-1312-4808-96F2-57AC016DA97B.jpeg

E9B35EA3-C5A6-4349-B676-CB869CEF7044.jpeg

That explains the slipping out of third as well, since the main shaft is probably moving fore and aft also. And the roller bearings between them are probably toasted.

Out she comes for some R&R.
 
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Lookout Ranch said:
OK, so I found at least part of my problem.
Input shaft end play. The retaining ring on the front must have failed or be missing. Hmmmmm.
View attachment 77270

View attachment 77276

That explains the slipping out of third as well, since the main shaft is probably moving fore and aft also. And the roller bearings between them are probably toasted.

Out she comes for some R&R.
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How miserable that must be. Bench pressing a transfer case and a transmission.

Personally Carter, I think you've found the causes of both of your problems in two different areas.
 
I used a harbor freight motorcycle jack to remove the trans, t case and cross member as a unit. It actually went smoothly, I never used the jack on an actual motorcycle but the 10 inch bars built into it worked perfectly.
 
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