Farmall 706 - Dash Oil light on when TA is in Direct

andy r

Member
Lost steering and brakes last fall when the tractor was on the auger. Did get it to prime and operate once last fall by just moving the tractor around. Could manually still steer. Tractor lost prime again and I just set it aside for the fall/winter. A couple weeks ago I tried to get things going again. New filter, compressed air to the transmission filler neck, removal of the 5/8 inch head bolt, extra 5 gal of fluid. No luck. Took the MCV off, added new springs, new o-rings, new gaskets, and a new mcv pump today. Steering and brakes came right up after letting the pressure out of the 5/8 inch head bolt. Steers good and brakes work good. TA shifts good from low to high and I can stall the tractor by applying the brakes in both hi and lo. The new problem is that when the TA is in direct or hi range the dash tell-tale light comes on and stays on. When you shift to low the light goes out. When I took the mcv off I never messed with any linkage that would be adjustable. What is interesting is that in direct or high if you pull that TA lever back very slightly while never shifting out of direct the light will go off. So the light goes off while still traveling in direct while holding the TA lever back slightly. I did take the TA selector valve out but did not change the springs as the roll pin would not come out easily. I checked the mcv and the selector valve snap ring is raising maybe 3/8 - 1/2 of an inch off of the casting when pulling the TA back to get the light to go out. Did I put something in the mcv together wrong???? Backwards??? TA worked good before this problem last fall. I did replace the plastic check valve in the lower right of the mcv with a steel plug for brakes and steering as per Hi Capacity's recommendation. I don't think it fell out as well as any O rings. Thank you.
 
With the TA forwarded that snap ring should just almost be touching that in bottom of that nut another thing install gauges on the MCV and see what your pressure are check your spool valve adjustment
 
In direct drive the snap ring does touch the nut screwed into the casting. With the snap ring touching the top of the nut the dash light is on. When you pull the snap ring up a ways the light will go off and the tractor will still continue in direct drive powering the wheels. I might have to pull it up 3/8 to 1/2 inch. I am pulling it up with the TA lever while driving. If you are talking the TA spool valve all I did was pull it out. I didn't disassemble the spool and replace the springs as I couldn't get the roll pin out. It all went back in the way it came out and I didn't adjust any threaded rods or anything.
 
The long and short of it is, andy, you're not going to be able to figure out what's going on without gauges. Once you measure the pressures the guys can tell you what's going on.

So you need to buy, borrow, or steal some hydraulic gauges.
 
Set the linkage according to specs and see where you are at then. I always set that spool w/snap ring when in direct so as to get a finger nail between snap ring and nut.
 
I have a 666 and am a new-to-tractors person so don't know much yet, but I did have to adjust the clutch and the TA on mine. There is a very specific amount the TA lever is supposed to move forward, or should I say, I specific place where it needs to stop. That was the last thing the shop manual says to adjust, is very specifically where that lever needs to stop. I had to make my own "stopper" so it couldn't go further than it was supposed to. In the manual, it shows a rubber stopper, but my tractor doesn't have one... did it fall off? was there never one? I don't know, but it needs to be there based on the locations of everything else after adjusting the clutch and TA. Could yours be the same, and it just isn't supposed to be going quite that far forward?
 

We sell tractor parts! We have the parts you need to repair your tractor - the right parts. Our low prices and years of research make us your best choice when you need parts. Shop Online Today.

Back
Top