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Dead Hydro

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I recently tilled my garden and parked my 712H in the garage. meanwhile the rabbits cleaned out two rows of my beets. I love pickled beets so it was out to till and replant. Jumped on the tractor and started it moved the lever forward nothing moved it back nothing revved the motor a bit nothing. It is like the buttons pressed down on the hydro. I have checked the fluid, buttons, and belts and all are OK.Any Ideas??

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Sundstrand? And the drive belt is tight? And the buttons are up? And the fluid is good?

I would look at a sheared key or differential issue. Check to see if the axle is turning. Rare, rare, rare that these pumps fail.

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Did you use the brake pedal when you backed it in ???

Since the brakes are rarely used on the hydros, the pedals tend to stick. Does not come fully back up when released and leaves the belt just loose enough to not turn the hydro.

If you look at it, the belt will be moving, but not spinning the rear pulley.

I've bought at least 3 "non working" hydros over the years that I drove off the trailer after tightening the belt.

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What Dan and other said above on the belt tension. The idler pulley bracket rusts to the sleeve it rides on. If brake is used, the spring will not pull the arm back enough. You can push or tap it back down, but the only way to make it work right is to pull the bracket off the sleeve, polish the sleeve and grease it & put it back together.

Sheared key on the diff is the other I'd look for. Not so easy to fix as it usually damages the keyways.

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