Farmall 450 transmissions problems

Hello,
I recently had something go bad on my Farmall 450. I new the transmission clutch was kinda getting worn out, just hard to shift. One day I was driving it and wanted to put it in reverse, I always needed to pull on the shift lever pretty hard to get it to go it and slowly let off the clutch. This time something bad happened. I can't remember any snapping or breaking noises. I can only shift it into 4 of the normal gear locations. I can't tell which ones, but 2 on the top and 2 on the bottom.
When I try to put it in one of those 4 positions, and let off the clutch, it promptly kills the engine. It kinda reminds me of trying to start out in 5th gear, I could never do that. I always had to be moving to get it into 5th for some reason. I just assumed that is what I had to do to get into 5th. Never thought of that as anything weird. If I leave the shifter in the neutral position, I am definitely is a gear of some-sort, I kinda feels like 1st or second for the speed that the tractor moves. But when I do that even for very short periods, you can definitely smell a burning clutch. When I push in the clutch, the engine seems to run normally again.
It sounds like a couple of gears are engaged at the same time?? I know there is a panel on the bottom, just not sure what I should be looking for, if I remove it. Seems like the shifter stills moves stuff around inside, So I would assume that is not broke.
Any help in a diagnosis would be appreciated. Just what to look for. I called a tractor shop, and he's saying it could be upwards $3K for fixing. I'm pretty mechanical inclined, so not too afraid of taking things apart.
The Farmall 450 has an Independent PTO, and a Torque Amplifier, and is Gas.

Thanks for any help

It almost sounds like the TA clutch is dragging/out of adjustment and a worn shift lever. If the TA clutch is dragging it will put a load to the low side of the gear selected making it difficult to get out of gear. Adjust the TA per IH instructions in the manual, can't remeber the specs, Jim will probably weigh in with the specs. The Shift lever being excessively wore will not fully actuate the shift rails engaging two gears and stalling the tractor. If you can not find a good shifter it is possible to weld up the end and file it to new specs.The TA clutch could be the source of the smell if not correctly adjusted. Hope this helps.

Cory

your stuck in two gears . unbolt shifter and pull it out then get a cat bar and line up the shifting rails again. rebolt shifter back in and good to go. shifter on bottom gets worn a bit and then when shifting in a hurry this is what happens. need to build up shifter.

If it is hard to get out of gear, the TA is out of adjustment. As to the gearshift, the rails are now out of alignment. You can pull the belt pulley, or the cover if no pulley and align them. But the lower part of the shifter may need to be fixed also, if worn. Once the rails are aligned, it may shift easier if the TA is pulled back. In any event, at the least the TA needs to be adjusted or maybe rebuilt. If the "hard to shift" means the gears clash, that may also be a TA problem, or you may have too much pedal clearance in the main clutch, or both. The linkage can also be loose, with worn parts. The main clutch usually wears until you can no longer get the proper pedal clearance, in other words, it slips.

forgot to mention that your stalling the tractor by slipping the clutch and its getting hot and thats your smell.

The trans is OK the TA is probably OK and lets go forward with advice based on things mentioned below.
There are three bolts holding the shifter to the platform. Remove all three. Look in the hole with a LED light or other good flash light. There are three shift rails in the hole each has a notch. Two are aligned about in the middle (front to back)
one will be out of place. (it will be either the right rail or the far left rail, the center will be OK.
Push in the clutch pedal and block it down all the way with a block of wood (be sure it is all the way forward.)
next use a small pry bar or a large screw driver to move the misaligned rail back (or forward) into alignment with the others. if it will not move with modest force, the tractor will need to be rocked forward and back while prying on the rail. It will move if the gear tension is removed by rocking the wheels forward and back.
Put the shifter back in the hole and make sure it is in the neutral position (moves left and right all the way) the trans is temporarily fixed. There is a picture on a recent post of the specifications for the tip of the shifter, it will need to be welded up and ground down to that size. (it is the same size for M and 400 Farmalls.)

Let the clutch back off of the block.
The clutch is adjusted so that when pushed down by hand pressure to the point that you feel some resistance, that there is one and 1/8 inch between the platform and the place where the clutch touches the platform. This is free play.
It is adjusted with the rod attaching to the clutch pedal, and will need the pin removed to allow it to be made longer or shorter.
When this is done, the TA Must be adjusted.
With the tractor on level concrete, the TA clutch (internal) needs to begin disengaging just as the main clutch is completely disengaged. This spot is a by the book process and is very important for the life left in the clutch , TA clutch, and gears. When the clutch pedal is fully depressed (as it should always be when shifting) Both clutches are disengaged. This allows free shifting and no excess pressure on the lever.
If you feel like it is not your thing, (by the book is not complex but requires the book) then have a helper that does feel comfortable assist.
It might just get by with a minor weld job on the shifter tip to make it good to go. Jim

Thanks so much for all the info. I will definitely try the removing shifter and seeing if I can adjust the shifter rails first and foremost. I am also handy with a welder and file, so I will see if I can find the specs on that one as well.

When I get that done, and still have problems I will post again.
This forum is very helpful
I don't want to let this tractor go to waste, as it looks pretty good if you ask me...

Thanks again
Tony