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Massey Ferguson 6465, 6475, 6480 - Ground Speed PTO

MF 6400 Series Tractors Service and Repair

Ground speed power take-off may be available (depending on option) on MF 6465, 6475, 6480 tractors. In contrast to the independent PTO mechanism where the speed of the rear PTO output shaft depends on the speed of the engine, Ground Speed PTO is driven by the pinion and a set of gears also used by the 4WD clutch unit. The speed of the rear PTO output shaft is therefore proportional to the tractor's travel speed.

Massey Ferguson 6465, 6475, 6480 Ground Speed PTO - Construction and Operation

Construction

The pinion of the rear crownwheel and pinion supports the driving gear (17), which is constantly meshed with the bell gear (33) of the 4WD clutch unit. On the ground speed PTO, the gear (27) is constantly meshed with the driven gear (10), which is attached to the 540 rpm driven gear (7) by the screw (12). This gear is itself splined to the output shaft (13) of the rear PTO.

Operation

The forward movement of the coupler (31) allows the movement transmitted by the gears (17) (33) to travel towards the output shaft (13) of the rear PTO via the shaft (8) and the gears (27) (10). The coupling is activated by an external rod located at the bottom right of the rear PTO housing. This rod is connected to a cable, which is connected to a control lever accessible from the cab. A switch connected to this control lever electronically controls the engagement of the ground speed PTO. When the Ground speed power take-off is engaged, the independent 540 - 1000 rpm PTO is deactivated.

Parts list: (1) Fork (2) Selector rail (3) Circlip (4) Snap ring (5) Control pin/finger (6) Splined sleeve (7) 540 rpm driven gear (8) Shaft (9) Pinion (10) Driven gear (11) Bearing cone (12) Screw (13) Output shaft (14) "O" ring (15) Pushrod screw (16) Nut (17) Driving gear (4WD) (18) Bearing cone (19) Bearing cup (20) Shim(s) (21) Countersunk screw (22) Chamfered washer (23) Ball bearing (24) Circlip (25) Nut (26) Sleeve (27) Driving gear/shaft assembly (28) Set screw (29) Hub (30) Bearing cup (31) Coupler (32) 4WD shaft (33) Bell gear (4WD), A - Details, B - Details, S - Removable support

Massey Ferguson 6465, 6475, 6480 Ground Speed PTO - Removing and install the selection mechanism and adjusting the pushrod screw

Removing the selection mechanism

Disconnect the PTO housing from the centre housing. Remove rod B. Remove the snap ring (4). Separate the control pin/finger (5) from the selector rail (2). Turn it approx. 90° and pull it out of the PTO housing in order to remove the "O" ring (14). Remove the control pin/finger (5) by pushing it along its entire length towards the inside of the PTO housing. Unscrew the nut (16) and the pushrod screw (15) on the selector rail (2). Unscrew the set screw (28). Remove the selector rail (2) and the fork (1).

Install the selection mechanism

Clean and check all components. Replace those that are defective. Install the fork and the selector rail. Lightly smear the thread of the set screw (28) with Loctite 221 or equivalent. Tighten this screw to a torque of 25-35 Nm. From the inside of the PTO housing, Install the control pin/finger (5) in its position and press it fully back towards the outside of the housing. Lubricate a new "O" ring (14). From the outside of the PTO housing, Install the new "O" ring (14) in the groove of the protruding section of the control pin/finger. Push the control pin/finger assembly back inside the PTO housing. Position it in the slot on the selector rail (2). Reinstall: new snap ring (4); control rod B. Lightly smear the thread of the screw on control rod B with Loctite 221 or equivalent. Tighten this screw to a torque of 25-35 Nm. Check the movement of rod B.

Adjusting the pushrod screw

Position the selector rail (2) so that its flat section is opposite the tapped hole of the pushrod screw (15). Tighten the pushrod screw (15) without forcing it in order to compress the ball, then loosen it by one quarter turn. Clean the thread of the pushrod screw (15) and the nut (16). Lightly smear the thread of the nut (16) with Loctite 242 or equivalent. Tighten this nut to 15-20 Nm while holding the pushrod screw in place. Check that the fork lock matches. Reconnect the PTO housing to the centre housing. Start the tractor engine and check the ground speed PTO operation.

Massey Ferguson 6465, 6475, 6480 Ground Speed PTO - Disassembly and reassembly the gears

Ground speed power take-off comprises a driving gear train (17) (33) and a driven gear train (27) (10) located respectively at the front and rear of the centre housing.

If work is necessary on the driving gear train (17) (33), proceed as follows:

1) To access the gear (17) - Disconnect the tractor between the gearbox and the centre housing. Remove the gear (17).

2) To access the gear (33) (MF 6465, 6475) - Remove the 4WD clutch unit.

3) To access the gear (33) (MF 6465, 6480) - Disconnect the tractor between the gearbox and the centre housing. Remove the 4WD clutch unit. If work is necessary on the driven gear train (27) (10) (all types of transmission except GTA1540 (50 kph)), remove the rear PTO housing. The lower bearing and removable support S are also removed with this housing during the operation.

Ground Speed PTO gears disassembly

Disconnect the PTO housing from the centre housing. Place the housing in a horizontal position with the gears facing upwards as required. Loosen the nut (16) and the pushrod screw (15) for the 540-1000 rpm selector rail. Remove the ground speed PTO selection mechanism. Loosen the countersunk screw (21). Recover the chamfered washer (22).

Remove the splined sleeve (6). Unlock the nut (25). Immobilise the output shaft using a locally obtained M16 screw. Partially loosen the nut (25) using a standard socket (55 mm flat). The nut (25) must be unlocked before removing removable support S in order to take advantage of the opportunity to lock the output shaft (13) with the M16 screw. Remove removable support S using bearings at the front ends of the PTO shafts (upper and lower). Finish unscrewing the nut (25) and remove it. Also remove: hub (29) and the coupler (31); bearing cone (18) (to be paired with the cup (19) if it is to be re-used); shims (20); bearing cone (11) (to be paired with the cup (30) if it is to be re-used); gear/shaft assembly (27).

Drive out the bearing cups (19) (30) from the removable support. If necessary, visually note the position of the shaft (8) and remove it along with the sleeve (26). Remove the circlip (3). The undercut end of the shaft (8) is positioned towards the 4WD clutch unit. If necessary, remove the driven gear (10), which is centred and fitted to the 540 rpm gear (7) via a screw. The method of fitting one gear against another has already been used in chapter 7 in the section on the GPA40 output shaft and brake). Strip the sleeve (6) by carrying out the following steps: Remove the circlip (24). Drive out the ball bearing (23).

Ground Speed PTO gears reassembly

Clean and check all components. Replace those that are defective. Assemble the sleeve by carrying out the following steps: Install the ball bearing (23) using a suitable fitting drift whose external diameter should be slightly less than the external diameter of the ball bearing. Install the circlip (24). If necessary, reinstall: driven gear (10); circlip (3) in the sleeve (26); shaft (8). Install the bearing cups (19) (30) against the removable support cord. Shim the bearings (11) (30) and (18) (19) of the gear/shaft assembly (27). Install the removable support. Tighten the V screws to a torque of 68-92 Nm. Clean the threads of the new nut (25) and the gear pin (27). Lightly smear the nut thread with Loctite 270 or equivalent. Immobilise the output shaft. Correctly position the nut. Definitively tighten to 160-240 Nm.

Using a suitable punch, lock the nut in place by bending the collar into the grooves of the shaft without breaking it. Reinstall the coupler (31) and the splined sleeve (6). Correctly position the chamfered washer (22) and install it to the ball bearing (23). Lightly smear the thread of the countersunk screw (21) with Loctite 270 or equivalent. Tighten this screw to a torque of 24-28 Nm. Reinstall and adjust the ground speed PTO selection mechanism. Install the pushrod screw (15) and the nut (16) of the 540-1000 rpm selector rail. Adjust the pushrod screw. Reconnect the PTO housing to the centre housing. Start the tractor engine and check the Ground speed power take-off operation.

Massey Ferguson 6465, 6475, 6480 Ground Speed PTO - Shimming the gear/shaft assembly bearings

The gear/shaft assembly (27) is shimmed with removable support S. The removable support must be removed from the rear PTO housing assembly and clamped in a vice fitted with protective jaws.

Preparing for shimming

Assemble the gear/shaft assembly (27) with the bearing cones (11) (18) lightly lubricated. Separate the bearing cones by a shim (20) thickness in order to obtain a temporary clearance of approx. 0.10 to 0.15 mm. Install the hub (29). Immobilise the gear/shaft assembly (27) using a makeshift tool. Temporarily tighten the nut (25) to 30 - 50 Nm with no Loctite on its thread.

Shimming

Place the feeler pin of a dial gauge on the end of the gear/shaft assembly (27). Using the appropriate levers, apply diametrically opposed pressure on the gear of the gear/shaft assembly (27) by pulling on this assembly in order to fit the cone (18) in its bearing cup. With the help of an operator, set the dial gauge needle to zero. Repeat, pulling on the hub (29) in order to Install the cone (11) in its bearing cup.

According to the temporary clearance reading measured on the dial gauge, determine another shim (20) thickness to obtain a preload P1 = 0.05 to 0.15 mm. As far as possible, shim to the maximum tolerance. Loosen and remove the nut. Remove the hub (29) and the bearing cone (18). Install the shims between the two bearing cones (11) (18). Reinstall the hub. Lock the nut (25) again to a torque of 30-50 Nm, with no Loctite on its thread, in order to manually check the rotation of the gear.

MF 6465, 6475, 6480 Ground Speed PTO - Assembling and adjusting the control

Parts list: (1) Lever (2) Clevises (4) Cable (5) Support (6) Switch (7) Stops (8) Pin (9) Clips (10) Connecting rod

Install the control, lever side

Preparing the cable - If possible, tighten the clevis (2) to the maximum against the cable (4). Tighten the nut (3).

Assembly - Link the clevis to the lever (1) using the clip (9). Tighten the sheath end to the support (5) using nuts (11).

Install and adjusting the control, centre housing side

Preparing the cable - If possible, tighten the clevis (2) to the maximum against the cable (4). Tighten the nut (3).

Assembly - Slide the sheath end of the cable onto the support fitted to the right of the housing assembly. Place the lever (1) and the rod (10) in Ground speed power take-off position. Connect the clevis (2) to the rod (10) using the clip (9).

Settings

Adjust the sheath end on the support using the nuts (11) and without moving the rod (10). Tighten the nuts. Check that the control moves freely in each position (neutral and engaged). The coupler has spur cut teeth: it can only be controlled if the tractor is almost stationary.

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