Specifications, Service and Repair of Farm and Lawn Tractors


Massey Ferguson 3125, 3085 tractor Pull-type Clutch


This is a diaphragm pull-type clutch. The master cylinder is supplied by the low pressure hydraulic system. Drive to the gearbox is through the disc (6) which engages with the splined gearbox input shaft during rotation.

Massey Ferguson 3125, 3050 tractor pull-type clutch Construction

The slave cylinder (19) is fitted on the front face of the input shaft housing. The piston/cylinder assembly is sealed by composite seals 14 and 16 and the slave cylinder guide by rings 13 and 17Y.

The boot holder (11) is screwed on to the end of the piston (15) and retains the clutch release bearing carrier (9) and clutch release bearing (23). The spring clip (10) retains the clutch release bearing carrier (9) on the boot holder (11).

The clutch cover plate (7) is connected to the release bearing by a circlip tilled on the cover plate and which locates m the groove of the release bearing (23). Warning: Any operation which requires splitting the MF 3125, 3085 tractor between the engine and the gearbox requires removal of the spring clip (10).

Clutch disengagement

Depressing the clutch pedal moves the control rod which in turn operates the piston of a master cylinder. The quantity of oil displaced by this piston passes through the lower hole in the slave cylinder (19) and moves the piston (15) and release bearing (23) assembly rearwards. The diaphragm is then compressed and the disc (6) is released.

Clutch engagement

Releasing the clutch pedal causes oil to escape from the slave cylinder pressure chamber and the release bearing to return. The diaphragm is compressed and the disc (6) is held against the engine flywheel by the motion plate in the clutch cover (7).

Massey Ferguson 3125, 3070 tractor pull-type clutch Specifications

Clutch control type - Pull
Plate load - 1300 kg
Number of vanes - 7
Type of vane - Progressive
Type of pressure plate - Ventifated
Disc diameter - 330 mm
Friction linings - Cerametallic

Fig.1/1A. MF 3125, 3065 tractor Pull-type Clutch (Parts List)

(1) Engine flywheel, (2) Flywheel ring gear, (3) PTO shaft drive hub, (4) Engine flywheel attaching bolts, (5) Clutch cover plate dowel pins, (6) Clutch friction disc, (7) Clutch cover plate, (8) Bolts attaching cover plate to flywheel, (9) Clutch release bearing carrier, (10) Spring clip, (11) Rubber boot carrier, (12) Rubber boot, (13) Clutch slave cylinder guide ring, (14) Clutch slave cylinder seal, (14A) Slave cylinder "O" ring, (15) Slave cylinder piston, (16) Slave cylinder piston seal, (16A) Slave cylinder piston "O" ring, (17) Slave cylinder piston guide ring, (18) bolts attaching slave cylinder to gearbox, (18A) Speedshift housing, (19) Slave cylinder, (20) Retaining ring (clutch release bearing), (21) Flat washer (clutch release bearing), (22) Spring washer (clutch release bearing), (23) Clutch release bearing, (24) Guide pin, (25) Supply pipe grommet, (26) Supply pipe, (27) Cylinder supply elbow connector, (28) Slave cylinder straight bleed connector, (29) Bleed pipe, (30) Bleed pipe union, (31) Bleed take-off point

Massey Ferguson 3125, 3060 tractor Clutch cover plate


- Split the MF 3125, 3080 tractor between the engine and the gearbox.

- Separate the release bearing carrier from the cover plate (7).

- Position tool MF 457 to retain the cover plate/disc assembly (Fig,1).

- Progressively slacken the bolts (8) attaching the cover plate (7) to the engine flywheel (1).

- Remove the cover plate (7) and the disc (6).

- Remove the three dowel pins (5) on the flywheel (1).


- Clean the flywheel (1) with a solvent.

- Check the flywheel friction surface. If the flywheel friction surface is scored it can be skimmed.

- Lightly coat the PTO shaft hub splines (3) with a molybdenum disulphide grease. Fit the three dowel pins (5) on the flywheel (1).

- Using tool MF 457, center the clutch disc (6) on the flywheel. (The longest section of the hub must face the diaphragm). (Fig.1).

- Refit the clutch cover plate.

- Progressively tighten the bolts (8) to a torque of 25-35 Nm.

- Refit the gearbox to the engine.

Massey Ferguson 3125, 3085 tractor Engine flywheel



- Split the tractor between the engine and gearbox.

- Remove the engine clutch,

- Immobilize the engine flywheel (1).

- Remove the six bolts (4).

- Remove the engine flywheel (1) and the hub (3).


- If the friction surface of the flywheel (1) is scored, it can be skimmed ; a maximum of 1.5 mm can be removed. Surface finish 2.5 micrometers maximum. Shorten the dowel pins (5) accordingly. After skimming clean the flywheel with a solvent.

- Fit two cower pins into the flywheel attaching holes.

- Refit the nub (3) and the flywheel (1).

- Clean the bolts (4) and coat them with Loctite 241.

- Refit bolts (4) and immobilize the flywheel. Tighten 10 a torque of 110-140 Nm.

- Carry cut procedures 1 and 2 in reverse.

Flywheel ring gear replacement Disassembly

- Remove the flywheel.

- Drill a 5 mm diameter hole in the ring gear halfway between the inner diameter of the ring and the bottom of any tooth to a depth of 16 mm.

- Place a cold chisel m the space above the hole and split the ring gear.

- Wear protective equipment when removing the ring gear to avoid flying metal particles.


- Heat a new ring gear to 245°C in an oven. Do not use a blow torch or any other naked flame.

- Fit the ring gear (2) on to the flywheel (1) with She chamfered lead on the teeth pointing towards the front (engine side) of the flywheel. Push the ring gear Quickly into position. Allow the ring to cool slowly

- Refit the flywheel.

Clutch release bearing Disassembly:

- Split the Massey Ferguson 3125, 3070 tractor between the engine and the gearbox.

- Release the carrier from the clutch cover plate.

- Grip the tool made up locally in a vice. Locate the release bearing carrier on the tool.

- Screw up the nut on the tool to compress the spring washer (22).

- Press the circlip (20) near the center with a small screwdriver.

- Press on the carrier (9) and remove the circlip (20)

- Remove the washer (21), the spring washer (22) and the release bearing (23) from the carrier.



- Carry out procedures 3, 7 and 4.

- Locate the circlip (20) in the groove of the carrier (9) and ensure that it is correctly located.

- Check the radial clearance of the release bearing (23) in the housing of the carrier (9).(Fig.6)

- Refit the gearbox to the tractor.