Universal joint shaft brake

On some model tractors, the universal joint shaft brake comprises 6 discs and 6 intermediate plates, distributed on either side of a mechanism and activated by a control piston and a pin. The control piston is located on the right-hand side of the gearbox. The brake piston pushes the control rod, which activates

the brake plate. This then moves apart, and compresses the discs against the intermediate plates, which are splined together by pins (14). When released, the control plate springs ensure minimum clearance between the brake discs. Lubrication is ensured by an external hydraulic pipe coming from the lubricating circuit.

Exploded view of the universal joint shaft brake 

1 Shaft

3 Flange

4 Dowel pin

5 Allen screw

7 Brake plate

8 Ball

9 Spring

10 Dowel pin

12 Intermediate plate

14 pin

16 Universal joint shaft brake control piston

17 Control rod

22 Seal

23 Cylindrical screw

25 Stud

26 Nut

Cross-section view of the universal joint shaft Brake 

Disassembling the universal joint shaft brake

The following operations must first be carried out: Drain the transmission oil (approx. 65 litres). Split the tractor between the clutch housing and transmission housing. Remove the universal joint shaft. For easier reading, the work is carried out on a scale model. References are relative to figure.

Remove the suction filter of the variable displacement pump, if it obstructs disassembly (depending on model). Take off the internal leak pipe and deflector. Remove the lubricating oil pipe. Remove the control piston of the universal joint shaft brake (16). Take off the sleeve.

Remove the screws from the flange (5). Push out the flange (3) with two M8 screws. When pushing out the flange, the drive shaft must not leave its seat.

Take off the flange (3), discs (11), intermediate plates (12) and brake plate (7).

Reassembling the universal joint shaft brake

Before reassembly, all components, mating faces and grooves must be clean. Any rust, mud or water must be removed. Fit the studs (4).

Starting with an intermediate plate (12), fit 3 intermediate plates (12) and three discs (11) alternately. The first intermediate plate is fitted in position A. Use new intermediate plates (12) and new discs (11). Oil the discs before assembly.

The second intermediate plate is fitted in position B, and so on alternately.

Fit the brake plate (7). The control pin must be opposite the drilled hole.

Fit the control piston of the brake (16) with a new seal (22). Assemble the activating corner correctly as shown on the brake plate (7). Fit the remaining discs (11) and intermediate plates (12). Clean the mating face of the cover and smear with sealing product (ref. X 903.050.074).

Fit the flange (3) and tighten the screws (5) to a torque of: 50Nm

Check the axial clearance of the universal joint shaft with a dial gauge.

Specified value: 0.3 + 0.1mm

If outside the specified value, correct the clearance with compensating shims.

Fit the lubricating pipe, return pipe and deflector. Fit a new suction filter.

Grease and install a new O�ring. Insert the sleeve on the shaft (1).

Adjusting the brake control piston:

Unscrew the locknut. Tighten the adjustment rod with a torque wrench (or the corresponding torque gauge, ref. X 899.980.151); to a torque of: 4 to 5Nm

Unscrew the rod by 3.6 turns and lock it in this position. Assemble the tractor between the clutch housing and transmission housing. Refit the universal joint shaft. Fill up the transmission oil.

Disassembling the universal joint shaft brake control

Remove the hydraulic pipe. Loosen and remove the brake cylinder attachment screws. Remove the brake cylinder and control rod. Discard the paper gasket.

Reassembling the universal joint shaft brake control

Clean the mating faces of the gearbox and brake cylinder. Smear the control lever ball joint with miscible grease. Fit the control rod in the brake cylinder.

Oil and fit a new paper gasket. Fit the control rod / brake cylinder assembly in the gearbox housing. Fit and tighten the brake cylinder attachment screws.

Reconnect the hydraulic pipe. Bleed the brake.

Main braking circuit of Dyna VT transmission

Tractors with a DYNA VT transmission are fitted with a hydraulic braking system operating on the high pressure auxiliary circuit for the rear brakes and on the transmission low pressure circuit for the front axle shaft brake. They are both controlled by a braking valve activated by two pedals that can operate coupled or uncoupled. The braking valve, located at the front of the pedal, receives and directs pressure to the various components. It controls:

- The right- and left-hand brakes located under the rear axle, and operating simultaneously or separately,

- the front axle shaft brake control,

- the trailer brake control via a pressure sensor located on the valve.

Rear brakes

Located in the rear axle, the two disc brakes are independent. Each brake is controlled hydraulically by a cylinder, or mechanically by the ParkLock ram. The braking valve is supplied by the make and break valve located under the distribution block with an accumulator that maintains a pressure reserve of 135 � 165 bar. The braking valve includes a pressure relief valve (0-70 bar). The pressure is distributed to the brake by two spools located on either side of the pressure relief valve.

Front axle shaft brake

The front axle brake is located at the front of the gearbox. It is a hydraulically controlled multidisc brake.

The main braking valve controls a power-assisted braking valve which operates the front brake under a 18 bar max. pressure (transmission low pressure circuit).

Trailer brake

The trailer brake is controlled electro-hydraulically. A pressure sensor informs the Autotronic 5 calculator of the pressure in the braking circuit. This then activates a proportional solenoid valve that controls the trailer brake valve via the transmission 18 bar circuit.

Characteristics of braking components

Braking valve

- Braking pressure: 0 to 70 bar.

- Working travel: 16 mm

Rear brakes

- Piston diameter: 50.8 mm

- Piston stroke: 3.7 mm

- Maximum volume used by piston: 12.25 cm3 on each side

Front brakes

- Piston diameter: 62 mm

- Piston stroke: 6.1 mm

- Rear brake / front brake pressure ratio: 2.04 bar

- Maximum braking pressure: 18 bar

Braking valve control

Parts list 

(1) Main braking valve block (2) Braking pressure regulator (3) Left-hand brake control (4) Right-hand brake control (5) Pedals (6) Bearing (7) Bearing (8) Bearing (9) Bearing (10) Sensor (11) Spring

Identification of ports 

(P) High pressure supply

(T) Tank return

(X) Control of front axle shaft brake and trailer brake pressure sensor

(F1) Left-hand brake supply

(F2) Right-hand brake supply

Braking control

The pedals are pressed against the braking valve rods via bearings (6) (7) (8) (9). Each pedal simultaneously controls the pressure regulator and corresponding spool valve (3) or (4).

Relations between the different tractor braking circuits

The braking circuits of the rear axle, front axle and trailer are hydraulically or electrically linked. These circuits must react simultaneously to a single action on the brake pedals.

Parts list 

(P1) High pressure variable displacement pump

(P2) Transmission low pressure hydraulic pump

(PB) Trailer brake and ParkLock priority valve

(CD) Make and break valve

(TV) Trailer braking valve

(BV) Tractor braking valve

(EV) Trailer brake control proportional solenoid valve

(AC1) Accumulator (ParkLock)

(AC2) Accumulator (rear brakes)

(TB) Trailer brake

(BR1) Rear brake

(BR2) Rear brake

(BP1) Pedal

(BP2) Pedal

(M) Pressure sensor

(FD) Front brake control valve

(BF) Front brake

(AUX) To non-priority components

(AUTO 5) Autotronic 5 calculator

(PARKLOCK) ParkLock assembly (ram and control)

Action on tractor brakes

Pedals coupled

When one of the two pedals (BP1) and (BP2) is activated, the pressure regulator located in the braking valve regulates the pressure coming from the make and break valve (CD) and accumulator (AC2). The braking valve then distributes this pressure to the rear brakes (BR1) and (BR2).

Simultaneaously, the braking valve sends a pressure signal to the spool valve (FD) and pressure sensor (M). The spool valve (FD) controls the front axle brake (BF) with pressure from the pump (P2) (transmission 18 bar circuit). The sensor (M) allows the Autotronic 5 to control the trailer brake via the proportional solenoid valve (EV).

Pedals uncoupled

If the driver presses on just one pedal, this acts on the braking valve pressure regulator and on a brake spool valve. The pressure is directed to the corresponding brake. The �&� valve in the braking block ensures no pressure signal is supplied to the spool valve (FD) or sensor (M). The front brake (BF) and trailer brake (TB) are only activated when both brake pedals are simultaneously activated.

�&� Valve

The �&� valve is fitted in the braking block. It allows pressure to be supplied to the trailer brake and front brake only if the two pedals are activated. The pressure directed to the rear left- and right-hand brakes must be identical to enable operation of the front brake and trailer brake.

Diagram

Parts list 

(1) Tractor braking valve

(2) Pressure relief spool

(3) Right-hand brake spool

(4) Left-hand brake spool

(5) Right-hand brake

(6) Left-hand brake

(7) & Valve

(8) Accumulator (braking circuit)

(9) Accumulator (ParkLock circuit)

(10) Transmission low pressure circuit pump

(11) Front axle shaft brake control spool

(12) Front axle shaft brake

(M1) Braking circuit load pressure switch

(M2) Braking circuit load pressure switch

(TR 34) Trailer braking pressure sensor

(A) Trailer brake control

(B) To ParkLock

(C) Braking circuit supply pressure from make and

break valve (135 - 165 bar)

Rear brake cylinders

The rear brake cylinders are located on the rear axle, beside the trumpet housings.

Description 

The rear axle braking system consists of a brake cylinder (1), a piston (2), and a rod (5) that acts on an assembly (3) comprised of discs (6) and intermediate plates (7) (see chapter 6). The brake disc assembly is fitted before the final drive unit (4) in the rear trumpet housing. The piston acts on the rod (5) whose triangular end allows the two intermediate plates (9) and (10) to swivel in relation to each other. When swivelling, the intermediate plates (9) and (10) are kept separate by balls (8). Return springs (18) restore the intermediate plates (9) and (10) to position when the brakes are released. The port (16) is linked to the bleed circuit by a pipe.

Operation

Braking can be activated hydraulically (brake pedals) or mechanically (ParkLock).

Pedal braking

The braking pressure (coming from the braking valve) arrives at the cylinder via the port (14). The piston (2) is forced down by the pressure, driving down the lower part of the piston (17) and rod (5) and activates the braking mechanism.

Mechanical braking (ParkLock)

When the brakes are activated by the ParkLock ram, the levers (18) activate the cams. As they rotate they drive the lower part of the pistons (17) and rod (5) and activate the braking mechanism. When the lower part of the piston (17) has lowered, the spring (15) keeps the upper part of the piston (2) at the top of the cylinder.

Removing the universal joint shaft brake 

The front axle shaft brake is located at the front of the gearbox.

Operation

The front axle shaft brake operates in a similar manner to the rear brakes. A piston pushes a rod (21) with a triangular end. The triangular part allows two intermediate plates to swivel in relation to each other, while they are held apart by balls (23).

Bleeding the brakes

The tractor brakes are bled through bleed plugs located at the rear right-hand side of the tractor beside the auxiliary spool valves:

(1) Front axle shaft brake

(2) Rear left-hand brake

(3) Rear right-hand brake

The trailer brake is bled through the bleed plug located on top of the distribution block. The brakes must be bled every 1200 hours, or when working on the braking circuit.

Bleeding method

Start the engine. Open the right-hand (3), left-hand (2) and front (1) bleed plugs. Press moderately on the coupled brake pedals, with pedal travel of approximately 20 mm. Never press the pedals down more than 25 mm when the bleed plugs are open. A jet of oil under pressure will spurt out of the bleed plugs.

Let the air bleed out at the plugs.

Close the plugs again when the fluid coming out no longer shows any trace of foam or air bubbles. Release the pedals. Open the bleed plug on the trailer brake valve. Repeat the operations. Check the oil levels in the auxiliary hydraulics and gearbox.

Crankshaft Main Bearings - Remove and Install

Removal Procedure

Remove:

- the engine oil pump.

- the crankshaft rear seal. Ensure that the main bearing cap is marked for the correct location and orientation.

- the two setscrews (1) and the main bearing cap (2) from the cylinder block.

- the lower main bearing shell (3) from the main bearing cap (2). Keep the main bearing shell and the main bearing cap together. The lower main bearing shell is a plain bearing that has no oil holes.

For number six main bearing, remove the two thrust washers (4) from the cylinder block. In order to remove the thrust washers (4), use Tooling to rotate the crankshaft in the correct direction. If necessary, push the crankshaft toward the front of the engine or push the crankshaft toward the rear of the engine while you rotate the crankshaft, in order to aid removal. The thrust washers have a locating tab at one end.

Push out the upper main bearing shell (5) with a suitable tool from the side opposite the locating tab. Carefully rotate the crankshaft while you push on the bearing shell.

- the upper main bearing shell (5) from the cylinder block. Keep the bearing shells together. The upper main bearing shell has a groove and two oil holes.

Installation Procedure

Ensure that the main bearing shells are clean and free from wear or damage. If necessary, replace the main bearing shells. Clean the journals of the crankshaft. Inspect the journals of the crankshaft for damage. If necessary, replace the crankshaft or recondition the crankshaft.

Lubricate the crankshaft journal and the upper main bearing shell (5) with clean engine oil. Slide the upper main bearing shell (5) into position between the crankshaft journal and the cylinder block. Ensure that the locating tab for the upper main bearing shell is correctly seated in the slot in the cylinder block. The upper main bearing shell has a groove and two oil holes.

For number six main bearing, ensure that the two thrust washers (4) are clean and free from wear or damage. If necessary, replace the thrust washers. Lubricate the thrust washers (4) with clean engine oil. Slide the thrust washers (4) into position between the crankshaft and the cylinder block. Ensure that the locating tab is correctly seated in the cylinder block.

Install:

- the lower main bearing shell (3) into the main bearing cap (2). Ensure that the locating tab for the lower main bearing shell is correctly seated into the slot in the bearing cap. The lower main bearing shell is a plain bearing that has no oil holes.

Lubricate the crankshaft journal and the lower main bearing shell with clean engine oil. Install the main bearing cap (2) to the cylinder block. Ensure the correct orientation of the main bearing cap. The locating tab for the upper and the lower bearing should be on the same side of the engine. Lubricate the threads of the setscrews (1) with clean engine oil. Lubricate the underside of the heads of the setscrews (1) with clean engine oil.

Install the setscrews (1) to the main bearing cap (2). Evenly tighten the setscrews in order to pull the cap (2) into position. Ensure that the cap is correctly seated. Do not tap the main bearing cap into position as the bearing shell may be dislodged. Tighten the setscrews (1) to a torque of 80 N�m (59 lb ft). Turn the setscrews (1) through an additional 90 degrees. Use Tooling to achieve the correct final torque.

Check the crankshaft end play. Push the crankshaft toward the front of the engine.

- Tooling to the cylinder block and the rear face of the crankshaft. Push the crankshaft toward the rear of the engine. Use Tooling to measure the crankshaft end play. The permissible crankshaft end play is 0.17 mm (0.007 inch) to 0.41 mm (0.016 inch).

- the crankshaft rear seal.

- the engine oil pump. 

Connecting Rod Bearings � Remove and Install

Removal Procedure

Remove the engine oil pump. Use Tooling to rotate the crankshaft until the crank pin is at the bottom center position.

The connecting rod and the connecting rod cap should have an etched number (X) on the side. The number on the connecting rod and the connecting rod cap must match. If necessary, make a temporary mark on the connecting rod (5) and the connecting rod cap (2) in order to identify the cylinder number. Do not punch identification marks onto fracture split connecting rods. Do not stamp identification marks onto fracture split connecting rods. Remove the two setscrews (1) and the connecting rod cap (2) from the connecting rod (5). Discard the setscrews (1). Remove the lower bearing shell (3) from the connecting rod cap (2). Keep the bearing shell and the connecting rod cap together.

Carefully push the connecting rod (5) into the cylinder bore until the connecting rod (5) is clear of the crankshaft. Remove the upper bearing shell (4) from the connecting rod. Keep the bearing shells together. Do not push on the fracture split surfaces of the connecting rod as damage may result. Do not allow the connecting rod to contact the piston cooling jet. Repeat Steps for the remaining bearing shells. Fracture split connecting rods should not be left without the connecting rod caps installed.

Installation Procedure

Inspect the pins of the crankshaft for damage. If the crankshaft is damaged, replace the crankshaft. Install:

- the upper bearing shell (4) into the connecting rod (5). Ensure that the locating tab for the upper bearing shell is correctly seated in the slot in the connecting rod. The ends of the upper bearing shell must be centered in the connecting rod. The ends of the upper bearing shell must be equally positioned in relation to the mating faces of the connecting rod. Lubricate the upper bearing shell (4) with clean engine oil. Use Tooling to rotate the crankshaft until the crankshaft pin is at the bottom dead center position. Carefully pull the connecting rod (5) against the crankshaft pin. Do not allow the connecting rod to contact the piston cooling jet. Clean connecting rod cap (2).

- the lower bearing shell (3) into the connecting rod cap (2). Ensure that the locating tab for the lower bearing shell is correctly seated in the slot in the connecting rod cap. The ends of the lower bearing shell must be centered in the connecting rod cap. The ends of the lower bearing shell must be equally positioned in relation to the mating faces of the connecting rod cap. Lubricate the pin of the crankshaft and lubricate the lower bearing shell (3) with clean engine oil.

- the connecting rod cap (2) to the connecting rod (5). Ensure that the etched number (X) on connecting rod cap (2) matches the etched number (X) on connecting rod (5). Ensure the correct orientation of the connecting rod cap. The locating tab for the upper bearing shell and the lower bearing shell should be on the same side.

- two new setscrews (1) to the connecting rod. Tighten the setscrews evenly to a torque of 18 N�m (13 lb ft). Do not reuse the old setscrews in order to secure the connecting rod cap. Tighten the setscrews evenly to a torque of 70 N�m (52 lb ft). Turn the setscrews through an additional 120 degrees. Use Tooling to achieve the correct final torque. Ensure that the installed connecting rod assembly has tactile side play. Rotate the crankshaft in order to ensure that there is no binding. Repeat Steps for the remaining connecting rod bearings.

- the engine oil pump.

Reassembling the Dyna VT power take-off - Installing the set of discs on the disc carrier

PTO clutch

PTO clutch parts

1 Shim

2 Taper roller bearings

3 Clutch cover

4 Cylindrical screw

5 Shim

6 Internal blade holder

8 Shim

9 Spring washer

10 Set of blades

11 Disc

12 Intermediate plate

13 Piston

14 Ring

16 Lip seal

18 Plate

19 Lip seal

20 Brake disc

21 Allen screw

22 Grower washer

23 Bush

25 Pinion

28 Taper roller bearing

29 Nozzle

30 Locking half-rings

31 Circlip

32 O�ring

35 Shaft

36 Taper roller bearing

37 Ring with rectangular section

38 Grub screw

39 Nozzle

40 Sensor

42 Shaft

Rear PTO drive

Rear PTO drive parts

101 Taper roller bearing

102 Shim

104 Clutch body

105 Roller

107 Circlip

108 Washer

109 Needle bearing cage

110 Spacer

112 Circlip

113 Taper roller bearing

114 Circlip

115 Allen screw

116 Stop

118 Pinion (1000 rpm)

118A Pinion (540 or 750 rpm)

120 Shaft

121 Circlip

122 Washer

123 Taper roller bearing

124 Shim

125 Grub screw

126 Spi seal

127 O�ring

128 Bearing cover

129 Cylindrical screw

132 Spacer

133 Threaded stud M10 x 50 - 10.9

134 Nut M10-10

135 PTO guard

137 End-fitting

139 Sensor

140 Allen screw

Start with an external blade. Next alternate with an internal blade (11). Each internal blade (11) should be fitted in respect to the narrow slot (pos. 2) while the wide slot (pos. 3) should be positioned either side alternately. Total number of discs: 7 external discs (12) and 6 internal discs (11).

Fit the disc carrier (6) together with the set of Belleville washers (9). Fit the compression tool (ref. X 899 980 145). Compress the clutch. Fit the locking half-rings (30). If the locking half-rings are chamfered on just one side, the chamfered side must face the disc carrier (6). If the disc carrier (6) does not fit into place, fit it without the set of discs (10) and mark the teeth. Push the set of discs home, ensuring it is correctly centred. Measure the distance (uncoupling clearance) using laminated shims. Specified values: 1.75 to 3.50 mm. If the minimum distance of 1.75 mm is not obtained, the discs are wrapped. Fit a new set of discs (10).

Smear the thread of the nozzle (29) with plastic binder (ref. X 903 050 084).

Tighten the nozzle (29) to a torque of:25 Nm. If necessary, fit the bearing (28) to its stop with its closed part facing upwards into the interior of the

clutch cover (3). Fit the bearing (2) up against the clutch cover (3). Adjust the position of the external discs (12) and fit the clutch cover (3) to its stop.

Fit compensating shims (1) on the bearing (2).

Measure and note the distance between the mating faces. For example: 178.6 mm. The distance between the flange face and the mating face of the journal is written in white on the top part of the rear axle housing. Example: 178.71. The distance between the journal of the bearing (2) and the flange face of the housing cover should be less than 0.1 to 0.2 mm, as the written value indicates.

This means that the journal clearance must be 0.1 to 0.2 mm. If not, correct it with compensating shims (1). The distance between the flange face and the mating face of the journal of the lower shaft is written in white on the lower part of the rear axle housing. Example: 148.75. This value is not necessary in case of repair, because a dial gauge must be used to measure the bearing clearance. Check the bearing clearance of the lower shaft (120). Fit the compensating shims (1) in the upper bore. Smear 4 new O�rings with miscible grease and fit them at the position of the oil pressure pipes.

Clean the housing mating face. Check the 2 locating pins are fitted correctly.

Smear the mating face with sealing product (ref. X903.050.074). Carefully raise the housing cover and fit it on the rear axle housing. Tighten the M18 screws and nuts to a torque of: 400 Nm. If necessary:

Smear the outside of a new shaft sealing ring (126) with a thin layer of sealing product (ref. X 903.051.711), and insert it until it comes into light contact with the cover (128), the seal lips turned towards the oil chamber. Depth approximately 5 mm. Fill the lip seals 2/3 full with miscible grease.

Fit the corresponding compensating shims (124). Smear new O�rings (127) with miscible grease and fit them in the groove of the cover (128). Smear the thread of the screws (129) with plastic binder (ref. X 903.050.084) and tighten. Rotate the shaft (120) 10 times. Fit a dial gauge. Push in the shaft (120) once and note the clearance value J2.

Rotate the shaft (120) 10 times. Fit a dial gauge. Pull once on the shaft (120) and note the clearance value J1.

Total clearance J = J1+ J2. 0.02 mm < J < 0.07 mm

If not, correct it with compensating shims (124). PTO end-fitting with 6 x 1� 3/8" splines Also compatible:

PTO end-fitting with 21 x 1� 3/8" splines

PTO end-fitting with 6 x 1� 3/4" splines

PTO end-fitting with 20 x 1� 3/4" splines

The PTO end-fitting has 4 drive holes for the PTO sensor. Fit the end-fitting (137). Fit the spacer (132).

Lock the end-fitting (137 with a screw M16 (for easier assembly). Tighten the nuts (134) (M0-10) to a torque of: 69 Nm. Top up the transmission oil level.