trouble with a john deere Z425 zero turn

countryboy36266

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i bough this mower at a swap meet did not run i rebuild the motor the deck flush the hydraulic system put all new oem belt on it and cut my yard with over time the drive belt act like it slipping and if you keep running it the belt burn off i have change 8 time and i can't find the problem this mower has a hydraulic pump and two motors i need help
 

Auto Doc's

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Sounds to me like the belt tensioner pulley is getting hot and locking up. That will slowly burn up a belt.

Are you using OEM belts? Are you ordering the belt by using the product ID numbers on the machine label?

Not all Z425s were built the same.
 

Tiger Small Engine

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Sounds to me like the belt tensioner pulley is getting hot and locking up. That will slowly burn up a belt.

Are you using OEM belts? Are you ordering the belt by using the product ID numbers on the machine label?

Not all Z425s were built the same.
Possible bad tensioner pulley. Also check both hydraulic pumps to be sure they are mounted securely. Are they straight and level, are the mounting points all good, are any of the mounts broken, cracked welds?
 

Auto Doc's

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I see you are new to this site. Welcome.

Be aware that we need the machine product identification label information (PIN). Some people refer to this as the serial number tag. Without that vital information, we are just throwing wild guesses out here.

If a problem concerns the engine, we will need the specific engine number stamped in a valve cover or from the factory label affixed the side of the fan shroud.
 

Honest Abe

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i bough this mower at a swap meet did not run i rebuild the motor the deck flush the hydraulic system put all new oem belt on it and cut my yard with can be your friend hydraulic pump and two motors i need help
were you holding your breath when you wrote this.....? Punctuation can be your friend , . ; - ! 🫣
 

countryboy36266

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the pin MOZ425BO47OO3 when i run it if i push the control all the way forward that when it seem to be the worst
 
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