No matter what I say or how I say it, this is going to come across as being a tad arrogant. Oh well...... shit happens. :sidelaugh:
Listen guys........ Jack and I have spent hundreds of hours to put together a site that has the most extensive amount of printed information that came from the very people that designed these tractors. What I don't understand is why some of you don't go and read the manuals that deal with the very item you are asking about? If you want more information about SERVICING a particular part on your tractor, then why not consult the SERVICE MANUALS section of the library FIRST? That's why Bill Parkin wrote them and that's why we have them here.
As an example, we seem to have THREE members wondering about what's involved to rebuild their DRIVE MOTOR. While that's certainly a fair question, this manual http://www.manuals.casecoltingersoll.co ... marked.pdf explains what to look for when you dismantle your motor. It talks about the "wear plate" as well as other issues that affect the overall performance (or lack of performance) of the drive motor.
Costs of rebuilding any hydraulic part or even an engine is something that can only be determined by taking the item apart, inspecting it carefully, measuring the amount of wear when such measurements are needed and then replacing or refurbishing the worn parts. It also depends on whether the CORE itself is still usable. As an example, some engine blocks can be so badly damaged that they are not worth repairing even if a repair is possible. When it comes to hydraulic components, that can also be the case. But if the motor housing is not damaged, then the manual tells you which parts are the "usual suspects" when the motor no longer delivers proper torque to the rear wheels.
I do recall one owner reporting that his motor was very weak and he took it apart to see why. He discovered that the wear plate and manifold plate were scored. So he put them on a surface grinder and took a few thou off them to make them dead flat once again. He reassembled the motor and found that his tractor was now quite usable. Whether doing that alone managed to restore the motor to 50, 60, 70, 80 or 90 percent of what is like when new is unknown. But the manual talks about the wear plate, manifold plates and the commutator because these are the things that wear. The question is: "How badly worn are they?"
I think that some hydraulic repair shops are going to order in certain parts automatically when rebuilding these motors because experience tells them that these parts are the cause of the problem. New motors are often upwards of $1000.00 to buy new from an Ingersoll dealer so if it's possible to rebuild one for half that amount, then that would seem to be a good deal.
Case recommended that the the geroler and roller thickness be no more than .002" less than the thickness of the housing, so why not machine the housing to take up the clearance? That should be neither difficult nor expensive.