Specifications, Service and Repair of Farm and Lawn Tractors


Massey Ferguson 8260, 8270 Power Shuttle gearbox - Removing and install the front Clutch

Split the Massey Ferguson 8260, 8270 tractor between the engine and the gearbox. Drain the gearbox and the centre housing. Remove the clutch cover plate from the gearbox.

Remove the flange from each end of the pipe (78) and remove it.
Remove pipes (31) (74) (86) (87) and (94).
Remove the front clutch (2) and pull it from the housing using a locally made tool.
Clean the parts. Replace any defective ones.
Check that PTO shaft (1) is installed.
Refit the clutch using the tool used for removal.
Replace the pipe seals (74) (94).

Install the pipes, carry out operation 5 in reverse order. Replace the pipe seals (78) and refit them the pipe. Tighten the flange holding screw at each end of the pipe to a torque of 25 Nm - 35 Nm.

Install the gearbox clutch cover plate. Top up the housing oil level and check it with the sight glass located at the rear left of the centre housing.

Couple the MF 8260, 8270 tractor between the engine and the gearbox. Carry out a road test using the power shuttle and using ratios A, B, C and D of the Dynashift. Check oil tightness of the mating faces and hydraulic unions.

Disassembling and reassembling the MF 8270, 8260 front clutch

Separate cover (33) from unit (18). Remove the discs (29) and the intermediate plates (30).
Remove the front snap ring (9). Remove the splined ring (6), the anti-extrusion rings (8) and seal (7).
Remove circlip (11), take off cover (2) from the pump (14) complete with bearing (12).
Pull the lubricating pump out of the pump unit (1) and take it apart from the clutch housing (18).
Remove seal rings (15). If necessary, extract ring (16) and remove the 1.5 bar valve (73).

Place the partially disassembled clutch on a suitable locally made fixture.
Compress the Belleville washers (25) and remove the rear snap ring (9).
Remove locking ring (5). Gradually release the Belleville washers.
Split unit (18) fitted with piston (28) from shaft (19).
Remove the Belleville washers.
Remove snap ring (23). Pull out the shaft (19) complete with bearing (22) from hub (27).
Remove the circlip (21). Extract the bearing (22) from shaft (19).

Remove the piston. Remove seals (24) (69) and discard them. If necessary, extract the bearing (68) from unit (18).
If necessary, remove snap ring (54) and remove the input sun gear (53). Remove snap ring (65). Extract bearing (32).

Make sure that pin (20) is fitted. If removed, fit the bearing (32) on cover (33), using a press and a suitable tool. Install snap ring (65). If disassembled, refit bearing (68).

Lubricate the new seals (24) (69) and fit them on the piston. Fitting piston (28). The angular position of the piston depends on the position of unit (18) lubricating ports. Align the indexing holes drilled in the unit and the piston. To align, use a pin of a suitable diameter.

Complete the installation of the piston by gradually and alternately striking around its top rim with a plastic
mallet. Check that there are no fragments of the seal after assembly.

Using a suitable tool, force fit bearing (22) on shaft (19), the seal side facing towards the rear clutch. Fit circlip (21).
Put the assembly (shaft, bearing, circlip) in the hub (27). Fit the snap ring (23). Install the Belleville washers.

Massey Ferguson 8270, 8260 Tractors can be fitted with six Belleville washers. Assemble unit (18) fitted with the piston (28) on shaft (19). Compress the Belleville washers using the tool.

Position ring (5), aligning two of the flats with the flats on unit (18). Replace the rear snap ring (9) and correctly
position it in the bottom of the groove.

Remove the fixture. Check that the seal rings (15) turn freely in their grooves. Fit the seal rings, lightly coated with miscible grease, making sure that they do not protrude beyond the rim of unit (18).

If necessary, fit the 1.5 bar valve (73) and tighten to a torque of 47 - 54 Nm. Insert ring (16) using a suitable fixture, with the chamfer “C” in the direction.

Lubricate the bush. Assemble pump unit (1) on unit (18). Lubricate pump (14) with transmission oil and position it aligning the flats of the rotor with those on the unit (18).

Manually check the angular movement of the rotor on the flats of unit (18). Install bearing (12) on cover (2) of the pump. Install the cover. Install circlip (11) and screws (13) and tighten to a torque of 36 - 46 Nm.

Lubricate and install a new assembly (O’ring (7) and anti-extrusion ring (8)). Slide on the splined bush (6). Install a new front snap ring (9). Soak the discs (29) in a transmission oil bath for approximately 1 hour.

Check that they are correctly saturated. Position the intermediate plates (30), aligning the tabs and the discs (29) on hub (27) according to the type of tractor.

Lightly smear the mating face of the clutch cover (33) on the unit (18) with Loctite 549 or its equivalent. Place the cover on the unit, the tabs of the intermediate plates lodged in the cut out notches on the clutch cover.

Fit and tighten screws (66) to 25.5 - 34.5 Nm. Manually check the rotation of the hub (27). If necessary, refit the input sun gear (53) and fit snap ring (54).

Shimming the MF 8260, 8270 front clutch

This operation consists in obtaining an axial clearance of 0.60 to 0.80 mm between the pump cover (2) and clutch cover plate (4).

To carry out this operation, remove the PTO shaft so as to remove the effect of the spring fitted at the rear end of the shaft to alow the clutch assembly to move. Install the clutch on cover (38) of the rear clutch.

Place a approx. thick 2 mm shim (3) on cover (2). Lubricate the lip of the cover plate seal . Protect the lip of the seal by fitting a protective material over the splines of the shaft (19).

Fit two guide studs on opposite sides of the gearbox housing and temporarily install the clutch cover plate (4) without using Loctite. Gradually tighten several screws.

Place a dial gauge at the end of shaft (19) and check the clearance by moving the shaft sideways. Check that the snap ring (65) of bearing (32) is correctly in contact with cover (38) by pushing the shaft (19) back as far as possible.

Remove clutch cover plate (4). Depending on the reading previously obtained with the dial gauge, define a new thickness for shim(s) (3) in order to obtain a clearance of between 0.60 mm and 0.80 mm.