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Massey Ferguson 250 - Rear axle and final drive

MF 230, 235, 240, 245, 250 Tractors Repair Operations

Tractors Without Planetary Final Drive

Massey Ferguson 250 and Orchard model tractors are equipped with a planetary type final drive unit located in outer end of rear axle housing. All other models are equipped with a straight drive axle that splines directly into the differential side gears.

Remove and reinstall - The axle shafts can be removed from tractor without removing axle housings if desired. Raise and support rear of MF 250 tractor, then remove rear wheel and tire. Remove brake drum retaining screws and pull drum from axle flange. Remove cap screws attaching retainer to axle housing, then withdraw axle shaft with bearing assembly and shims from housing. Reinstall, reverse the removal procedure while noting the following special instructions: Install inner oil seal into axle housing with lip facing inward. Grease lip of seal before inserting axle shaft. Use a dial indicator to check end play between the axles. Be sure axle on opposite side is moved fully outward when checking end play. Change thickness of shims as necessary to obtain end play of 0.05-0.20 mm (0.002-0.008 inch). Note that end play is controlled by total thickness of shims installed between both axle housings and retainers, and varying the thickness of either shim pack will affect adjustment of both axles. Tighten retainer cap screws to 75 Nm (55 ft.-lbs.) torque. To remove axle shaft and housing as a unit, first drain oil from differential housing. Raise and support rear of tractor, then remove rear wheel and fender. Disconnect brake linkage and bitch lift link and lower link. Support axle housing with a hoist, remove attaching stud nuts and slide axle housing assembly from Massey Ferguson 250 tractor. When left-hand axle housing Is removed, be careful that differential assembly Is not accidentally pulled out with the axle housing. Reinstall axle housing assembly, reverse the removal procedure. Tighten housing stud nuts to 115 Nm (85 ft-lbs.) torque. Tighten wheel stud nuts to a torque of 230 Nm (170 ft.-lbs.).

Overhaul - The axle retainer and bearing cone are retained on axle shaft by a shrink-fit steel collar. To renew axle shaft, bearing, retainer or outer oil seal, first drill the collar, then split collar using a hammer and chisel. Pull the retainer, bearing and collar from axle shaft using a suitable puller or press. Install a new seal into retainer with lip of seal facing the bearing cup. Grease lip of seal before installing retainer over axle shaft. Seat bearing cone against shoulder of shaft. Heat a new retaining collar to approximately 400C (750F), then quickly install and seat the collar against the bearing cone. Renew inner oil seal in axle housing before reinstalling axle shaft. Be sure lip of seal faces inward.

Tractors With Planetary Final Drive

Remove and reinstall axle housing - Remove either axle housing with planetary assembly as a unit, first drain oil from differential housing. Support rear of MF 250 tractor and remove rear wheel and tire and the fender. Disconnect brake linkage and hitch lift link and lower link from axle housing. Support axle housing with a hoist or floor jack, remove attaching stud nuts and separate final drive assembly from differential housing. Reinstall, reverse the removal procedure. Tighten housing stud nuts to 115 Nm (85 ft.-lbs.) torque. Tighten wheel stud nuts to 270 Nm (200 ft.-lbs.) torque on tractors equipped with 5/8 inch diameter studs, or to 325 Nm (240 ft.-lbs.) on tractors equipped with 11116 inch diameter studs.

Remove and reinstall planetary assembly - Remove planetary assembly, suitably support rear of Massey Ferguson 250 tractor and drain oil from final drive planetary housing. Remove the wheel and tire and the fender. Securely apply parking brake to hold brake discs in alignment in case axle shaft is pulled outward. Scribe a mark across outer housing, ring gear and axle housing to ensure correct alignment when reassembling. Remove retaining stud nuts, then withdraw outer housing and ring gear assembly. To reinstall, reverse the removal procedure making certain that scribe marks are correctly aligned. Tighten attaching nuts to a torque of 75 Nm (55 ft.-lbs.). Refill drive housing with Massey Ferguson Oil, or equivalent. Capacity is approximately 1.0 L (1.1 U.S. quart).

Overhaul planetary - Disassemble the planetary unit, first drive roll pins inward into carrier. Thread a 3/8 inch cap screw into end of planet gear shaft and pull shaft from carrier. Remove planet gears being careful not to lose the loose needle rollers. There are two rows of 29 rollers in each gear. Withdraw sun gear through large opening in carrier. Using a suitable puller, separate the carrier from drive cover. Remove half rings from wheel axle, then press axle out of drive cover. Remove axle shaft, inner bearing cup, shims and oil seal, if so equipped, from axle housing. Note that axle oil seal has been eliminated on late production tractors to provide a common reservoir for planetary and differential housings. When servicing early production MF 250 tractors equipped with the seal, do not Install a new seal when reassembling. On all models, planetary housings must still be refilled with recommended oil, approxImately 1.0 L (1.1 U.S. quart) each planetary, to provide Initial supply of lubricant. Reassemble, install a new oil seal into drive cover until outer face of seal is 2 mm (0.080 inch) above surface of cover. Lubncate seal lip, then insert wheel axle into cover. Press bearing cone onto axle until rollers are seated in bearing cup. Install thickest pair of split rings that will fit into wheel axle groove. Assemble sun gear and planet gears into carrier using new roll pins to retain planet gear shafts. Be sure to account for all the planet gear needle rollers. Press carrier assembly onto wheel axle until it is seated against the split rings. Complete reassembly by reversing the disassembly procedure. Check planet carrier bearing.

Carrier bearing preload adjustment - Planet carrier bearing preload of 0.15-0.40 mm (0.006-0.016 inch) is adjusted by means of shims installed between inner bearing cup and axle housing. To check and/or adjust bearing preload, first drain oil from differential housing and final drive planetary housing. Loosen stud nuts securing planetary housing to axle housing, then insert three 0.76 mm (0.030 inch) feeler gages between planetary ring gear and axle housing. Tighten nuts next to feeler gages to 75 Nm (55 ft-lbs.) torque, then measure wheel axle end play with a dial indicator. If measured end play is within range of 0.36-0.61 mm (0.014-0.024 inch), preload is correct and no change in shim thickness is required. If end play is less than 0.36 mm (0.014 inch), preload is excessive and shim pack thickness should be reduced. If end play exceeds 0.61 mm (0.024 inch), preload is insufficient and shim pack thickness should be increased.