Ground PTO (2WD version)


Tractors may be fitted with ground PTO. Unlike the independent PTO system where the PTO speed depends on the engine speed, the proportional PTO is driven by the rear differential pinion and the PTO shaft speed is proportional to the travel speed of the tractor. The pinion comprises a gear (31) constantly meshed with either the gear (16) (2WD). The sliding gear (10) secures the shaft (8) in rotation with the shaft (18) (2WD). The gear (3) fitted at the end of the shaft (8) drives the 540 rpm gear on the rear PTO line. The movement of the sliding gear (10) is obtained by a pad hinged on a pin fitted on the left in the lower part of the rear axle housing and controlled by a rod and a cable operated by a lever in the cab.



Parts list 2WD
(01) Plug (02) Circlip (03) Gear (04) Circlip (05) Bearing (06) Circlip (07) Circlip (08) Shaft (09) Circlip (10) Sliding gear (11) Screw (12) Cover plate (13) Needle roller bearing (14) Cup (15) Cone (16) Gear (17) Circlip (18) 2WD shaft (19) Cone (20) Cup (21) Shim(s) (22) Spacer (23) Circlip (24) Plug (25) Double pin (26) Double pin (27) Sleeve (28) Sleeve (29) Shaft (30) Circlip (31) Gear



Disassembling the ground PTO (2WD version)


Chock the tractor. Drain the rear axle housing. Remove the lubrication pipe from the engine clutch or the Power Shuttle (depending on version) that is fitted to the lower cover plates of the centre housing and the gearbox.
Remove the screws (11).
Remove the cover plate (12). Recover the spring (3).
Remove the retainer pipe (4) from the control rod (7) and the detent plunger (2).
Disconnect the control cable (1) and remove the rod (7). The pad (1) is free fitted in the centreline of the rod (7).
Remove the "O" ring (5).
Remove the hitch hook.
Extract the plug (1).
Remove the circlip (2).
Take off the gear (3).
Remove the circlip (4).
Take out the shaft (8) with the bearing (5) and then remove the sleeve (10). If necessary, remove the circlip (7).
Take off circlips (6) (9).
Extract bearing (5) using a press.
Extract the plug (24).
Take off the circlip (23) and spacer (22).
Remove shims (21).
Remove cup (20).

Take out shaft (18) complete with bearing cone (19).
Take off the circlip (17) while supporting the gear (16).
Remove the gear (16) and the cone (15).
Extract the cone (19) and take the circlip (17) off the shaft (18). Pair up the cones and the cups if they are to be reused. The bearing (13) is force fitted into the shaft (18).
Extract the cup (14) using a suitable puller. If the gear (31) is removed, it is necessary to remove the right-hand hydraulic cover plate.
Chock the tractor. Apply the hand brake. Raise the tractor using a jack. Position the axle stand.
Remove the wheel. Remove the right-hand hydraulic cover plate.

Tractors with no creeper unit
Drive out the double pins (25) (26) from the coupling sleeves (27) (28).
Slide the sleeves towards each other on the shaft (29).
Remove the shaft and sleeve assembly.
Remove the circlip (30).
Remove the gear (31). On 2WD tractors (without proportional PTO) the gear (31) is absent, but the circlip (30) must still be fitted.

Tractors with a creeper unit
Remove the fork, the sleeve assembly, the connecting shaft and the coupler.
Remove the circlip (30).
Remove the gear (31).

Reassembling the ground PTO (2WD version)


If carrying out an operation on the gear (31)

Tractors with a creeper unit
Install the gear (31).
Install the circlip (30).
Install the fork, the sleeve assembly (28) the connecting shaft and the coupler. Replace the pins. Adjust the fork.

Tractors with no creeper unit
Install the gear (31).
Install the circlip (30).
Install the assembly (connecting shaft and sleeves) then position the coupling sleeves (27) (28) on the shaft (29).
Install the double pins (25) (26) on the coupling sleeves. Turn the sleeve (28. Replace the pins. The long pin is fitted to the sleeve (27).

Tractors with or without creeper unit
Install the cup (14) up against the shoulder of the housing.
Install the cone (19) on the shaft (18) up against the shoulder, using a press and a suitable fixture, then position the circlip (17).

Check for the presence of the needle roller bearing (13).
In order to turn the shaft to carry out J1 shimming, do not fit the gear (16). Position cone (15). Fit shaft (18) assembled with the cone (19) and circlip (17).
Install the cup (20), the spacer (22) and the circlip (23). For correct shimming, make sure that the spacer moves freely in the bore of the housing.
Carry out shimming of the shaft (18) in order to obtain: J1 = 0 to 0.10 mm
Put a dial gauge feeler pin against the end of spacer (22).
Through the opening of the cover plate (12), pull on the shaft, while turning it alternately from right to left to correctly seat the cones in the cups.
Set the dial gauge to zero.

Depending on the clearance measured, select the correct thickness of shims.
Take off the circlip (23) and spacer (22). Take out shaft (18) assembled with the cone (19) and circlip (17) while supporting the cone (15). Refit the gear (16), the shaft (18) and the cup (20).
Apply two spots of grease to the shims (21).
Install the spacer (22) and circlip (23).
Replace or clean the plug (24) and its mating face on the housing.
Smear the corner of the plug housing with Loctite 542 and then fit the plug.
Place the sliding gear (10) on the shaft (18). Turn the small shoulder E towards the shaft (18).
Fit circlips (6) (9) on shaft (8).
Using a suitable fixture, fit the bearing (5) using a press onto the shaft (8), in contact with the circlip (6).
Check for the presence of circlip (7).
Install the assembled shaft (8) in the housing.
Install the circlip (4).
Install the gear (3).
Install the circlip (2).

Check the movement of the sliding gear (10) through the opening of the cover plate (12).
Replace or clean the plug (1) and its mating face on the housing.
Smear the plug with Loctite 542, then fit it slightly set back from the face of the housing.
Install the rod (7) (fitted with a new "O" ring (5)) by placing the pad (1) in the groove of the sliding gear (10).
Clean and degrease the mating faces (cover plate and housing).
Smear the mating face of the cover plate with a sealing product (Master joint 510 or equivalent).
Screw two opposing guide studs into the housing.
Install the retainer pipe (4), the control rod and the detent plunger (2) and the spring (3).
Install the cover plate (12) and the lubrication pipe for the engine clutch or the Power Shuttle (depending on version).

Take out the guide studs. Tighten the screws to a torque of 130 - 170 Nm.
Reconnect the proportional PTO control cable (1).
Adjust the control.
Top up the rear axle oil level.
Install the hitch hook (for tractors fitted with an auto-hitch, check that it operates correctly).
Check the correct operation of the proportional PTO.
Check tightness:
- of the mating faces
- of the cover plate underneath the rear axle housing
- Hydraulic unions