1566 TA problems

[Anthony Tjelle]

Hi, I recently changed all the fluids in a 1566. Now I have NO response in the TA lever. Lever moves freely back in forth while traveling, doesnt shift . I believe it is stuck in ta ( torque back) because my top end is maybe 14 mph in 3 high. The Torque is holding when I test in low 3. Kills the engine. Any thoughts

 

[Powered By IH]

Welcome!
Do your brakes and steering work as normal?
What oil did you use?
Is the oil full on the dipstick?

 

[Anthony Tjelle]

Brakes and steering work fine. I used hy Tran for ih tractors and the oil is just over full on the dipstick

 

[used red MN]

Hi, I recently changed all the fluids in a 1566. Now I have NO response in the TA lever. Lever moves freely back in forth while traveling, doesnt shift . I believe it is stuck in ta ( torque back) because my top end is maybe 14 mph in 3 high. The Torque is holding when I test in low 3. Kills the engine. Any thoughts

Hello Anthony, welcome to YT! When you move the lever does it move the small valve up and down on the left side on the transmission under the cab? Just FYI that whole valve body chunk that the TA valve sets on top of is the MCV “multi control valve” Have you had this tractor a while did the TA work fine before? Did you happen to do any other stuff to the tractor during the fluid change?

 

[Mark EC.IN]

It needs to be primed.

Overfill the oil by 5 gallons of Hytran, remove the plug on the mMCV (takes a 5/8" wrench), then quickly start the engine. You will have a mess, unless you rig a hose with a fitting that will screw in where the plug came out, run this hose around to the rear, and stick it in the fill port.

 

[used red MN]

It needs to be primed.

Overfill the oil by 5 gallons of Hytran, remove the plug on the mMCV (takes a 5/8" wrench), then quickly start the engine. You will have a mess, unless you rig a hose with a fitting that will screw in where the plug came out, run this hose around to the rear, and stick it in the fill port.

Doesn’t the loss of prime generally affect the PS and brakes as well? He says they work. Maybe the TA is on a separate pump in this case, he doesn’t mention if the 3 point and remotes have any action.

 

[Powered By IH]

Doesn’t the loss of prime generally affect the PS and brakes as well? He says they work. Maybe the TA is on a separate pump in this case, he doesn’t mention if the 3 point and remotes have any action.

If the TA is killing the engine in L3, and brakes and steering work, wouldn't that mean he has good pump pressure-not needing to be primed?
Nevertheless, move the TA lever like used red said and see if the valve is moving on top of the MCV.

The valve might just need to be readjusted too.

 

[used red MN]

If the TA is killing the engine in L3, and brakes and steering work, wouldn't that mean he has good pump pressure-not needing to be primed?

The TA with a working one way sprague clutch is strictly mechanical drive in Lo TA or reduction, just like the older mechanical shift TAs. The reduction drive path is different in the hydraulic shift TAs since they don’t utilize a planetary gear set. In low TA what I call the “anti free wheeling” clutch pack is the only thing engaged by hydraulic pressure. That is the part of low TA that gives it engine braking or hold back which the mechanical shift TA’s did not have. To the opposite, engagement of the direct or high TA clutch is totally dependent on hydraulic pressure. So no fluid pressure to the TA would equate to no drive in HI TA.
Edit to add: If there is no pressure for the TA to engage and the tractor has a working Tell-Tale light on the dash it should remain illuminated constantly when the key is on. If the TA was working previously and the Tell-Tale light was functioning it should have only illuminated when the clutch was pushed opening the MCV dump valve.

 

[BarnyardEngineering]

Also check the dump valve on the back of the MCV. I've had that stick open before. It should cycle in and out with the clutch pedal. Bought a 1586 at an auction, took it for a joyride when it got delivered, coasted down every hill. I was convinced the TA was shot, but I crawled underneath and saw the dump valve was stuck open. One tap and it snapped shut and worked perfectly for years.

 

[Anthony Tjelle]

I'm hoping it warms up enough to get it out this weekend and mess with it . I did check the valve on the top of the mcv. Is moving and appears to be in adjustment. The 3 point worked fine , hydraulics work ,steering and brakes are fine . Pulled a 6-16 plow in hard ground for a minute and it pulled fine Everything seems to be the same as before the oil change other than the TA does nothing. I will try your suggestions and get back. Thanks for all the replies.

 

[brendonh]

The TA is giving trouble? Naw.....Sherly not! That never happens.

I couldn't imagine the Troublesome Always being broken or misbehaving.......

 

[used red MN]

The TA is giving trouble? Naw.....Sherly not! That never happens.

I couldn't imagine the Troublesome Always being broken or misbehaving.......

I bet it will start on a 65 degree day without being plugged in or using ether! I didn’t leave any comments of ill intention about that JD tractor that is “okay” but the fresh engine can’t meet the compression specs in the service manual.

 

[brendonh]

I bet it will start on a 65 degree day without being plugged in or using ether! I didn’t leave any comments of ill intention about that JD tractor that is “okay” but the fresh engine can’t meet the compression specs in the service manual.

LOL!!
You forgot the battery charger on one side, the pickup and jumper cables on the other. Planning at least 4 hours time slot in your day before you ever go to work.

Ya know, friendly pokin the bear between a JD guy and an IH guy should never die. It's a tradition!

 

[Mrfred54]

Stuck in low range (TA) handle pulled back. Usually when this happens the Sprague clutch for low is warn out and come apart and piled all the pieces together and now you have a direct lockup and will not release. When shifted to high side it has burned out the clutches because the low side has more torque and will stay in low and now you have like what you posted. Stays in low range and pull good and will kill the engine in high range 3rd gear. No adjustments can fix this scenario. Not an oil issue, MCV controls functions for steering, which has priority over other functions. When steering is satisfied then oil is regulated to the brakes, torque, lube. Return steering oil then is directed to these functions. Tell lite should come on every time clutch is depressed and should go out when releasing the clutch, but before the tractor begins moving, very critical adjustment, because you want the TA clutches locked up before the main clutch engagement.

 

[BarnyardEngineering]

Never seen or heard of the sprag clutch "piling up" like that. Usually it just starts slipping because it's worn out from overrunning the entire time the tractor is in direct.

 

[Mrfred54]

Never seen or heard of the sprag clutch "piling up" like that. Usually it just starts slipping because it's worn out from overrunning the entire time the tractor is in direct.

Don't happen often but I have had it happen to two tractors since I started repairing IH tractors in 1971. Have also seen the input shaft get twisted off at the clutch disc. These are very rare occurrences