Farmall 1206 TA

my uncle has a 1206 and a few years ago he had the TA fixed or repaired or whatever but not the tractor is stuck in low and will not shift into high anybody got anyideas? does it need opened up again? is it an easy fix? also he said the left wheel bearing is out. Is that an easy fix? thanks I do know a little about the transmission of the '06's as I fixed the high range in my dads 806 a few years ago.

Is the T/A stuck in low or is it stuck in low range in the range transmission???????

the TA itself is stuck in low, both high and low (on the right side) work.

From reading on this forum, The first thing I would check is the cable linkage from the lever to the control valve. These have had issues, and are easy to repair externally. The fluid pressures on the TA are either applied to the direct clutch (Higher speed), or the TA locking clutch (holding it in TA)
if it free wheels when operating (speeds up down hills as though in neutral) I would suspect an MCV hydraulic issue.
If it does not free wheel I would suspect linkage issues to the valving. The Vet knows much more than I on this issue. Jim

(quoted from post at 09:13:04 06/01/11) From reading on this forum, The first thing I would check is the cable linkage from the lever to the control valve. These have had issues, and are easy to repair externally. The fluid pressures on the TA are either applied to the direct clutch (Higher speed), or the TA locking clutch (holding it in TA)
if it free wheels when operating (speeds up down hills as though in neutral) I would suspect an MCV hydraulic issue.
If it does not free wheel I would suspect linkage issues to the valving. The Vet knows much more than I on this issue. Jim

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You are on the right track but the 86 series tractors are the first to use a cable to shift the TA. All the older ones are controlled by rods and levers. On the TA shift lever you just need to make sure that the spool valve in the top of the MCV goes down to touch the snap ring when in the forward, TA, position. It should start to move up as soon as you start to pull the lever back to the high position.

It the tractor was working fine before the most likely cause of a failure that occurs after a period of disuse if the dump valve sticking in the open position. When the clutch is pushed in the dump valve is pulled to the rear to dump the oil pressure from the TA clutch packs to allow the tractor to shift easier. If it sticks back it will continue to dump the TA oil pressure when the clutch is released and you will be left with only the low side sprag clutch pulling. The tractor will also free wheel going forward down hill.

The rear axle bearing are not terribly difficult to replace but you will need heavy enough equipment to handle the rear wheel and then the axle housing. The inner bearing outer race can be removed from the rear frame by welding a bead on the inside to shrink it. The bearing cone is a press fit on the axle shaft and requires a large gear puller to remove it along with the bull gear. If you are good with a torch you can also cut the bearing from the axle. Once the bearings are replace the bearing preload will have to be reset by using the proper shim pack under the outer bearing cap.

On a 1206 if the rear frame has not had holes drilled through from the axle reservoir to the transmission/differential area, now would be a good time to do it. That allows the axle housing to become a common reservoir with the rest of the drive train and eliminates the problem of the axle bearing either running out of oil or over filling from a bad seal on the bull pinion shaft. If the housing is drilled you can also remove the expansion plug behind the inner axle bearing cup. Tractors with drilled housings should also have the square part of the fill/check plug sawed off on the axle housing to indicate that the update has been preformed and checking/filling the axle housing is no longer necessary.

Thanks for the cable start info. Your post indicates that the TA lever is Rearward for Direct, and Forward for Reduction. I never would have expected it to work that way. Jim

(quoted from post at 22:59:42 06/01/11) Thanks for the cable start info. Your post indicates that the TA lever is Rearward for Direct, and Forward for Reduction. I never would have expected it to work that way. Jim

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It doesn't. The forward position is the faster drive. Thanks for catching that.