The flywheel on my Ford 4500 backhoe had excessive wear on the friction surface area from years of clutch use. Though only about .020" of material need to be removed to resurface the clutch disk friction area, approximately .200" of material had to be removed from the remaining perimeter surface where the pressure plate is bolted to the flywheel in order to create a flat surface across the entire face of the flywheel. This means the pressure plate is now about .200" further from the throw out bearing when the clutch pedal is depressed. The service manual says the limit for resurfacing the flywheel is .080", but the clutch functioned properly prior to resurfacing the flywheel when the friction surface was worn down about .180", which is still .100" more than the recommended limit. I've read where people have cut the end of the clutch adjustment rod and added more threads to the rod to give it more travel, enabling the throw out bearing and hub to move further toward the pressure plate, but I don't know just how much travel was needed for those applications. Is this a viable option? My concern is that the release bearing fork may end up binding where it fits on the release bearing hub, thereby limiting the amount of potential forward movement. Another possible solution is to use a spacer/shim between the crank and the flywheel to push the flywheel out, but I don't know what effect that may have on crank bearings or the rear main seal or starter drive engagement on the ring gear. Though I know crank to flywheel shims are not uncommon for some engines, I can't seem to find any information for using them on heavy equipment engines. As far as I can tell, no one makes crank to flywheel shims for a 201 (3 cylinder) diesel with 6/4 manual trans and 11" clutch assembly. Would this work if I had one made?
Time and money spent with a machinist, you might be better off, just puttin a new or better condition flywheel in...
I'm not too worried about the .02 wear, or the .2" cut off the flywheel. Why did they need to take off .2" though? warped? I'd be more worried the balance is thrown off with the need to remove that much metal. If you are comfortable that it's still balanced, then I'd try to shim the throw out bearing or fork, no way I'd shim between the flywheel and crank. The threaded rod should work just fine as long as there's a new throw out bearing, the fork isn't worn, and the new clutch plate isn't thicker than stock. You take your chances if the pressure plate is worn, etc.
Delmer, the flywheel was not warped, it had excessive wear on the friction surface area from years of clutch use. Prior to getting it resurfaced, the friction surface area was worn down about .180", which left a considerable recess in the area that the clutch contacts. As a result, the remaining perimeter of the flywheel where the pressure plate mounts was .180" higher than the friction surface area. Since the flywheel is supposed to be flat all the way across, NAPA had to cut off the raised portion of the flywheel where the pressure plate mounts, plus an additional .020" to clean up the friction surface area where the clutch makes contact; therefore, the total amount cut was .2". Shimming the throw out bearing may not be an option; the neck area of the hub that the bearing is pressed onto is only about 3/8" deep. I'm afraid shimming it would not leave enough of the hub neck for the bearing to hold onto. Shimming the fork doesn't appear to be an option either, since it rotates on a shaft and the fork blades are sandwiched between two posts on either side of the release bearing hub. There is no place to put shims that I can see. I'm still not sure why a crank to flywheel shim wouldn't work: I know they are fairly common for many engine applications. I wonder if the .080" resurfacing limit (according to the service manual) has more to do with flywheel balancing than it does with exceeding the clutch adjustment limit.