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Neutral creep issue on my AC 912H

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I have an AC 912 that has neutral creep and I'm not sure how to get rid of it. I downloaded the service manual and I have followed every step to the letter but still have the creep. When shifting back to neutral the hydrostatic control cam doesn't return back to center which is leading to the creep. No matter how I adjust it the cam will never return to center. I thought maybe there was some way to adjust the linkage rod that holds the hydrostatic control strap, not that it's covered in the manual but that seems it should bring it back to center. The only thing I didn't try was adjusting the idler lever assembly since the belts seem to have proper tension, anyone have any similar experiences or solutions? I thought maybe it is easier to figure out if you see the issue.


Edited by Cliff

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On the inside fire wall where you can't see is item #9 . That lever connects to the hydro . It is held in place by a "D" slot and held in place with a nut.  That nut will loosen up and I'll guarantee you that you'll never find neutral.

I not sayin that's your problem, but it's beginning to show up.

Travel lever.jpg

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I found the issue, whoever owned it before me must have replaced the bushing on the hydro control arm. When they put it back together there are two concave washers, they installed them opposing and the spacer wasn't allowing the arm that moves the rod to the hydro control strap to lay flat. Since it couldn't lay flat there was travel in the hydro lever and the cam couldn't return to center. Thanks for the input!

BLT, you pretty much hit it right on the head! It was tight but the way the washers were flipped it couldn't fully flush up.


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I have found the culprit is usually the cam roller and lack of lubrication on the cam roller/cam and the shaft that the cam roller is on.

Looking at your video I would take the cam roller off, lube everything flip the roller and reinstall.

I have had hydros that I could not neutral even after all adjustments, when I change and lube the cam roller - Bingo no more problems.  And mine showed less wear than yours. 

I have found a molylube that dries works great and doesn't attract dirt.

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I thought the concave washers were supposed to be opposing??

They are on two of my three Sovereigns.  Not sure about the third.  I'll have to check tomorrow when I get off duty.

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Those belleville washers are supposed to oppose each other with the outside of curve away from each other.  When compressed they act as a spring to hold tension on the lever so it doesn't move on it's own.  I have seen some guys clean the rust off of the shaft, and then apply some lube, here also would be a good place for a dry lube such as graphite.  The idea being a little less effort to move lever.

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My 7117 was experiencing the exact same thing; read this thread and BLT's suggestion of the loose nut was spot on for me.  I never would have thought of something so simple.  Tractor now has positive neutral - awesome!  I'm very grateful for the knowledge base here!

Kyle Sands <>< Brandon, MN

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