GPA40 rear PTO - Intermediate shaft and driving gears



On tractors installed with GTA1040 transmission or GTA1540 transmission, the upper shaftline of the rear PTO comprises:
- the PTO clutch (1);
- the intermediate shaft (2);
- the layshaft (13);
- the tapered roller bearings (3) (4) and (7) (8);
- the driving gears (10) (11) (540-1000 rpm PTO version) or driving gears (10) (11) and (9) (540 E PTO (power take-off) version);


- a coupler (5) (540-1000 rpm power take-off  PTO version) or two couplers (5) (540 E PTO version ). Shims (27) fitted at the front end of the layshaft (13) allow the clearance of the tapered roller bearings to be adjusted.


On the 540-1000 rpm PTO version, the 540-1000 rpm power take-off  PTO lever installed on the left-hand side of the PTO housing (as viewed from the operator's seat), activates a selector rail (19) and a coupler (5). The coupler (5) moves either towards the 540-rpm gear (10) or towards the 1000-rpm gear (11) according to the required speed. On the 540 E power take-off  PTO version, a second lever connected to its own coupler engages this coupling with the gear (9) to obtain the 540 E economic speed. This second lever is installed on the right-hand side of the rear PTO housing (as viewed from the operator's seat). The 540-1000 rpm and 540 E power take-off  PTO rods are each controlled from inside the cab by a cable.

Lubrication
The oil enters the rear PTO housing via a restrictor union. The flow rate is then distributed via a restrictive hole (diameter approx. 1 mm) to the driving gears and driven gears.


Parts list 
(1) Spacer (540-1000 rpm PTO) (2) Intermediate shaft (3) Bearing cone (4) Bearing cup (5) Coupler(s) (6) Dowel(s) (7) Bearing cone (8) Bearing cup (9) 540 E driving gear (10) 540 rpm driving gear (11) 1000 rpm driving gear (12) Removable support (13) Layshaft (14) "O" ring(s) (15) Pushrod screw
(16) Nut (17) Set screw (18) Cup plug (19) 540-1000 rpm selector rail (20) 540-1000 rpm fork (21) 540 E fork (22) 540 E selector rail (23) Washer with flat section (540-1000 rpm version) (24) Circlip(s) (25) Shouldered ring (540 E version) (26) 540 E hub (27) Shim(s) (28) Oil deflector
(29) "O" ring (540 E version) (30) Vespel ring (31) Oil restrictor (32) "O" ring

Legend
F Details
540-1000 rpm PTO (power take-off)
540 E PTO


Partial kinematics and operation of the safety lock

Partial kinematics
The engine speed is transmitted to the rear PTO clutch located at the front of the centre housing via a shaftline which passes via:
- the Power Shuttle, the Dynashift and the GTA1040 transmission gearbox;
- the Powershift, the Power Shuttle and the GTA1540 transmission gearbox.
The intermediate shaft (2) is splined to the layshaft (13) and drives the driving gears (10) (11) and/or (9) depending on the position of the coupler(s). When a gear transmits the movement to the lower shaftline, the other gear(s) is/are passive and turn(s) idle on its/their axis.

540 E power take-off PTO safety lock
The safety lock device is only fitted on the 3-speed PTO version (540-1000 rpm and 540 E). It is located at the top and within the rear PTO housing. It acts as a lock due to the round end of its two adjustable rails. The selector rails (19) and (22) for the forks are machined in order to house the locks and to allow their movement.

Operation 
When the selector rail (19) engages the 540-rpm gear, it forces the lock (3) out of its housing. The lock (3) then pushes lock (2), which locks the 540 E selector rail (22) in neutral position and thus prevents any movement. This principle can be applied to the 540 E and 1000-rpm gears.

Disassembling, reassembling and adjusting the safety lock and adjusting a pushrod screw

Disconnect the PTO housing from the centre housing .

Disassembling the safety lock (540 E power take-off PTO) 
Using a locally obtained M5 screw, extract the dowel (6) using the tapped hole T in the dowel.
Extract finger D from the selector rail (22) (540 E PTO control) by pulling the rod out of the housing.
Remove the set screw (17) fixing the fork (21) to the selector rail.
Using the adjustable sleeve (1) (no left or right-hand screw), shorten the length of the safety locks (2) (3).
Unscrew:
- the nut (16);
- the pushrod screw (15).
Remove the selector rail (22).
Visually note the assembly.
Separate and remove the safety locks (2)(3).


 Reassembling the safety lock (540 E power take-off PTO)
Reassemble the safety lock device by following steps reverse order. During the reassembly process, observe the following points:
- Lightly smear the thread of the set screw (17) with Loctite 221 or equivalent. Tighten this screw to a torque of 25-35 Nm.
- If necessary, replace the "O" ring (14) by sliding it over the pin of finger D via the outside of the housing so as not to break it on the sharp edge of the housing.
- Do not forget to refit the dowel (6).
Adjust the safety lock and the pushrod screw(s).

Adjusting the safety lock (540 E power take-off PTO) 
Place a selector rail in neutral position. Engage a gear using the other selector rail. Adjust the sleeve (1) (no left or right-hand screw) to give a slight clearance of approx. 0.1 mm. Tighten the nut.
Activate each gear alternately and several times. Engage a 540 or 1000-rpm gear. Test the safety device by trying to engage the 540 E gear: this gear should not engage. Test the safety device for the other two gears in the same way.

Adjusting a pushrod screw
Position the selector rail concerned so that one of the flat sections is opposite the tapped hole of the fork pushrod screw (15).
Tighten the pushrod screw 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 (15) in place.
Check that the fork lock matches.
Reconnect the PTO housing to the centre housing.
Start the tractor engine and check the PTO operation.

Removing and install the selection mechanism

Disconnect the PTO housing from the centre housing.

540 - 1000 rpm PTO (power take-off) (A)
Unscrew:
- the nut (16);
- the pushrod screw (15).


540 E PTO (power take-off) (B)
Unscrew:
- the nut (16);
- the pushrod screw (15).
Shorten the length of the safety locks (2) (3).

540 - 1000 rpm or 540 E PTO (power take-off)
Remove the lubrication pipe (5). Remove the removable support (12) holding the front end of the PTO shafts (upper and lower) in place. Removal of the removable support (12) always involves removing the rear bearing and the GSPTO coupler (if fitted). Remove the selector rail(s) (19) (22).


Remove unit B, which amongst other components, comprises the driving gears. Separate the fork(s) from the coupler(s) (depending on version).

Install the fork(s) on the coupler(s) (depending on version). Reinstall unit B.


Check that the shims and tapered roller bearing cups are present in the removable support (12).
Reinstall the removable support (12) with the safety locks (2)(3). Lightly smear the thread of the screws (4) with Loctite 242 or equivalent. Tighten these screws to 68-92 Nm. Install the lubrication pipe (5), replacing the "O" rings beforehand.
Reinstall the selector rail(s) and the pushrod screw(s) (depending on version). Carry out adjustments.
Reconnect the PTO housing to the centre housing.
Start the tractor engine and check the power take-off PTO operation.