If the tractor was completely submerged by flood water, the potential for damage is high. It is highly likely that water has gotten inside the engine or transmission. The tractor will need a complete overhaul to be absolutely certain that further damage will not occur. If you do not have the shop facilities or expertise to perform these repairs, you may wish to have your dealer provide the service. If you choose to perform the repairs yourself, follow the recommendations below to reduce the risk of damage.
Engines Thoroughly clean the exterior of the engine.
Use a water hose, pressure washer, or steam cleaner. Scrub away any grease deposits with an appropriate engine cleaner. Disconnect and remove the battery. The battery may need to be replaced. Disconnect the starter and alternator or generator.