The fan clutch is a Kysor/Borg Warner part number 1090-08000-01. There is at least one listed on a popular auction site, that can be found by a search of that number. Kit Masters offers a rebuilt unit their part number is 8001x. To be clear, the fan should be locked up when engine and main power switch is off. Should release when main switch is turned on IF the system has air AND the engine is not hot. If it doesn't release it could be the controll valve under the passenger kick panel that is malfunctioning and not the fan clutch. Simple way to test clutch is to put air (at least 60psi) to the air inlet on the front of the fan clutch, if it releases with air pressure applied and locks up tight when air pressure is removed then it is functioning properly. The clutch has studs that the fan blade attaches to with lock washers and nuts that are typically included with a new/rebuilt clutch. I'm guessing the broken bolts that attach the clutch to the hub could be found at a CAT dealer or a generic hardware source. If I recall the bolts are an Allen head socket bolt and are hardened to be sure. Be sure to install with locktite to prevent them from vibrating loose again. As for the hub that the clutch attaches to...CAT would probably be your only source, hopefully it's not damaged. Good luck!!
