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Massey Ferguson 3115, 3120, 3125 - Rear Axle Trumpet Housings

MF 3000-3100 Series Tractors Service and Repair

On MF 3115, 3120, 3125 tractors, the trumpet housings support the RH and LH axle shafts and house the final reduction units which transmit the drive from the differential assembly. The two trumpet housings are identical and are fitted on either side of the center housing.

Massey Ferguson 3115, 3120, 3125 - Construction Trumpet Housings

The half shaft (2) is supported by two taper roller bearings (5) and (8) fitted opposite each other. The unit is sealed on the outside by a triple lip seal (3) and on the inside by a single lip seal (7). The final reduction planetary carrier assembly (21) fitted with three pinions (18) is splined onto the half shaft (2). Shims (22) located at the end of the axle shaft allow the taper roller bearing preload to be adjusted.

The half shaft (2) and the planetary carrier assembly (21) are held by the washer (23) and the bolt (24). The ring gear (10) is a force fit in the trumpet housing. It comprises five locating dowels (9) which center the brake plate (26). Drive from the differential is transmitted to the final reduction planetary gears through a planetary shaft (25) on to which the brake disc (27) is splined.

Parts List - (1) Wheel stud, (2) Axle shaft, (3) Triple lip seal, (4) Seal housing, (5) Bearing cup, (5A) Bearing cone, (6) Trumpet housing, (7) Seal, (8) Bearing cup, (8A) Bearing cone, (9) Locating dowel, (10) Planetary ring gear, (11) Spur washer, (12) Plug, (13) Bolt, (14) Spacer, (15) Circlip, (16) Planetary gear pin, (17) Thrust washer, (18) Planetary gear, (19) Spacer, (20) Needle roller, (21) Planetary carrier, (22) Shim(s), (23) Retaining washer, (24) Bolt, (25) Sun wheel, (26) Brake plate, (27) Brake disc, (28) Locating dowel, (29) Bolt

MF 3115, 3120, 3125 - Trumpet housing assembly

Removal

Immobilize the tractor. Apply the handbrake. Fit chocks between the frame and the front axle. Drain the rear axle only. Using a trolley jack, raise the side of the tractor involved. Support the tractor with an axle stand. Remove the wheel. Remove the stabilizer bracket. Disconnect the draft control sensor harness (without disconnecting the harness).

Remove the cab attaching bolts (A) with the nuts. Raise the cab sufficiently to lift the support spacer (B) clear. Check the clearance between the hood and the windscreen (if insufficient remove the sheet metal). Position a suitable support on a trolley jack under the trumpet housing. For the LH trumpet housing disconnect the lift hydraulics valve supply hose (plug the ends).

Unscrew the attaching bolts (29). Separate the trumpet housing from the rear axle housing. Remove: brake disc (27); planetary shaft (25); locating dowel (28). To prevent the brake piston from coming out of the housing, it is recommended that two wide washers and two bolts be fitted diametrically opposite each other to hold it in place. Remove the brake plate (26).

Massey Ferguson 3115, 3120, 3125 - Trumpet Housings Refitment

Clean the mating faces of the center housing and the trumpet housing with a non-greasy solvent. Apply a bead of oil resistant silicone (Silicomet type) to the inner edge of the center housing. Do not block up the oil drain hole in the housing. Check that the disk (27) slides freely on the planetary shaft (25). Refit the locating dowel (28), the planetary shaft (25) and the brake disc (27).

Screw two dowel pins into diametrically opposite positions on the center housing. Refit the brake plate (26) in the trumpet housing. To retain the plate, apply three spots of "Amber Technical" or equivalent grease to the surface of the ring gear (10). Fit the trumpet housing to the center housing. Turn the shaft (2) to engage the planetary shaft (25) in the planetary gears (18).

Clean the bolts (32) and coat them with Plastex, Hylomar or an equivalent gasket sealant. Fit and tighten the bolts (29) to a torque of 170-210 Nm. Refit the cab attaching bolts with the nuts and locknuts to a torque of: Nut - 27-35 Nm, Locknut - 13-20 Nm (with Loctite 270). Refit the draft control sensor.

Lightly coat the draft control sensor with Loctite Anti-seize or equivalent grease. Refit the wheel. Tighten to a torque of 400-450 Nm. Remove the axle stand. Test the hydraulic lift and brake circuits. Check for leaks: between the trumpet housing and the center housing, from the lift system valve supply hose (LH trumpet housing).

MF 3115, 3120, 3125 - Planetary carrier assembly

Disassembly

Remove the trumpet housing. Remove the bolt (24). Remove the retaining washer (23) and the shim(s). Remove the planetary carrier assembly (21). Remove the bolt (13) and the spacer (14). Open out the circlip (15). Using a copper tipped mallet, tap lightly on the three pins (16). Remove the three pins (16) and the circlip (15). Remove the three planetary gears (18), the needle rollers (20), the spacers (19) and the thrust washers (17).

Reassembly

Clean the planetary carrier (21), the pins (16) and the planetary gears (18). Check the condition of the parts. Coat the needle rollers (20) with "Amber Technical" or an equivalent grease. Into each planetary gear (18) insert two rows of needle rollers separated by a spacer (19). Each planetary gear has 56 needle rollers. Fit the planetary gears (18) and the thrust washers (17). Fit three pins (16) with the circlip (15).

Open out the circlip (15). Tap lightly on the three pins to insert the circlip (15) into the planetary carrier groove. Position one end of the circlip in contact with the pin (16). Clean the threads of the bolt (13). Fit the spacer (14). Coat the bolt (13) with Loctite 270 before fitting. Tighten to a torque of 34-50 Nm. Check that the spur washer (11) is fitted. Refit the planetary carrier. Fit shims to obtain the required preload. Refit the trumpet housing.

Bearings and Seals

Disassembly

Separate the trumpet housing from the center housing. Remove the planetary carrier. Remove: spur washer (11), bearing cone (8A) (runs free on shaft). Withdraw the shaft (2) from the trumpet housing. Extract the cone (5A). Drive out the triple lip seal (3). Using an extractor, remove: cup (5); housing (4) for seal (3); cup (8). Drive out the seal (7).

Reassembly

Clean the seal contact surfaces, the cup seats and the cones in the trumpet housing and on the shaft. The seal, cup and cone contact surfaces must be free from burrs and damage. Coat the outside diameter of the seal with Loctite 542. Fit the seal the correct way round. Replacement of seal (7): Without replacing the shaft (2) - So that the seal lip is not in the same place on the shaft, press on the seal until it is 9 mm from the shoulder of the cup. Replacing the shaft (2) - Position the seal 8 mm from the shoulder of the cup. Lubricate the cups (8) and (5) and press them fully on to the shoulder.

Press the housing (4) to within 20 mm of the trumpet housing. Push the triple lip seal (3) up against the shaft shoulder. Ensure that the seal is fitted the correct way round. Lubricate the shaft (2) and press the cone (5A) against the shoulder. Lightly grease the cone (5A), the lips of seals (3) and (7) (use BP Agricharge or an equivalent grease). Protect the splines of the shaft (2) and insert it into the trumpet housing.

The lips of the seal (3) must face outwards. Remove the protection from the shaft and lightly lubricate the cone (8A). Fit shims to obtain the required preload. Replace the plug (12) by a grease nipple. Partly fill the cavity at the end of the trumpet housing between the cone (5A) and the seal (3) with BP Agricharge or an equivalent grease. Remove the grease nipple and refit the plug. Refit the trumpet housing.

Massey Ferguson 3115, 3120, 3125 - Axle shaft bearings preload

Place the trumpet housing assembly in a vertical position. Remove the bolt (24) and the washer (23). Seat the cones (5A) and (8A) in their cups by turning the trumpet housing on its shaft. Fit shims (22) required to provide thickness greater than dimension X to obtain end play. Fit the washer (23) and the bolt (24) and tighten to a torque of 270-440 Nm.

Using a dial gauge, check the end play by moving the planetary carrier laterally. Remove the bolt (24) and the washer (23). On the basis of the reading obtained, remove the number of shims required to obtain a preload of: P1 =0.025 to 0.125. Clean the threads at the end of the shaft (2). Refit the washer (23). Clean the bolt (24) and coat it with Loctite 241. Tighten to a torque of 270-440 Nm.

MF TRACTORS TROUBLESHOOTING
1652	1749	2620	2725	2805
3050	3120	3640	3709	4245
4455	5320	5455	5613	6150
6280	6480	6615	7618	7720