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Kubota BX23, BX23S - 54,60 Inch Mower Deck

Kubota RCK54, RCK60 Mower link

Structure of lifting mechanism of mower

The lifting of RCK54, RCK60 Mower Deck is performed by the hydraulic system installed on Kubota BX23, BX23S tractor. The mower should be kept lift when traveling. When the position control lever is moved to LIFT position, the lift arm is lifted up by the oil pressure of hydraulic system, and the rear lift link (L.H.) is pulled rearward. Therefore, rear lift links rotate and the mower is lifted by the lift links and rear links. As this link system is a parallel linkage, the mower can be kept parallel at every position.

Mounting front link

Place all front link and frame link under the tractor. Attach the stay link with the nut on the tractor front frame. Stay link nut - 43.3 to 50.3 Nm / 32 to 37 lbf-ft. Attach the front link to the stay link with joint pin, washer and snap pin. Before attaching the mower links, adjust lengths (L1) to 22 mm.

Mounting frame link

Place blocks below the frame link if one person does the setting. Heights of blocks are recommended value for attaching. Start engine. Set the cutting height to 0 and lower the frame link. Then stop the engine. Attach the frame link to the link arm. Joint the front link and frame link with joint pin and snap ring. Attach the universal joint to Kubota BX23, BX23S tractor. Adjusting mower link - Move the hydraulic control lever rearward to raise the mower to the highest position. Stop the engine and remove the key. Adjust the left side links with bolt so that the clearance is as follows. Clearance between stopper and rear link 0 to 0.5 mm / 0 to 0.01 in.

Kubota RCK54, RCK60 Mower Deck Setting up

Assembling 54-inch mower deck

Place the mower on blocks. Attach all the anti-scalp rollers to the arms of the deck. Put clevis pins from outside and snap rings inside in the F position. 4.5 holes (X) must be visible. Attach the discharge deflector to the deck with the spring, discharge pin and cotter pin. Setting mower - Check all functions work correctly. Remove the front loader, front attachment and 3 point hitch attachment. Adjust all the anti-scalp rollers to the F position. 4.5 holes (X) must be visible. Unlock the lever to lift up the rear anti-scalp roller. Pull the L-pin and extend the ramp to front and rear sides.

Setting Kubota BX23, BX23S tractor

Make sure that the frame link is lifted up to the TOP position when tractor is traveling without mower. Stop the tractor behind the mower. Set the parking brake. Set the cutting height to 0 and lower the frame link. Then stop the engine. Make sure that the rear lock is unlocked. Make sure that the universal joint is in rear position. Make sure that the frame link is fully down.

Mounting 60-inch mower deck

Start the engine and engage 4WD. Set the range gear shift lever to LOW. Release the parking brake. With the right front tire, make a driving target to the guide. Drive over the ramp of mower along the guide. Keep the front tire side touching the guide rod. Just after the Kubota BX23, BX23S tractor drove over the mower, stop the engine. Make sure frame link is connected to mower. Set the parking brake. Lock the rear lock. Set the PTO select lever to Rear-PTO position. Connect the universal joint by the lever guide. Lock the lever guide by the lock lever. Set the PTO select lever to Mid-PTO position. Put front and rear ramps back to the ramp bracket. Lock the L-pin. Start the engine. Lift up the mower to the TOP position. Lock the dial gauge and set the parking brake. And then, stop the engine. Lock the rear anti-scalp roller. Adjust the anti-scalp roller.

Kubota RCK54, RCK60 Mower Deck - Cutting height

Adjusting front and rear cutting height

Turn the cutting height control dial to 2.0 and adjust the anti-scalp roller's height to factory specified clearance between the rollers and the ground. Clearance between rollers and ground - 6.0 to 13 mm / 0.25 to 0.50 in. Align the ends of the right side blade towards the front and rear of the machine. Turn blade by hand in either direction. Adjust (L1) of the front links with lock nuts so that (A) is within factory specification. Difference between front tip and rear tip of blade 0.0 to 5.0 mm / 0.0 to 0.20 in. To adjust (L1), loosen lock nuts then turn lock nuts. Rotate both lock nuts at the same time to set L.H. and R.H. in even length. Tighten lock nuts securely. Front link lock nut 60 to 70 Nm / 45 to 51 lbf-ft.

Adjusting left and right cutting height

Operate the hydraulic control lever rearward to raise the mower deck to the highest position. Stop the engine and remove the key. Turn the cutting height control dial to the desired height. Set the anti-scalp roller's height to keep clearance between rollers and the ground inside specification shown below. Clearance between rollers and ground - 6 to 13 mm / 0.2 to 0.5 in. Lower the mower deck by moving the hydraulic control lever forward. Turn left blade by hand parallel to Kubota BX23, BX23S tractor axle and turn right blade parallel to axle to measure from the outside blade tip at and to the level surface. The difference between measurement should be less than the factory specification.

Difference between left tip and right tip of blade

Less than 3 mm / 0.12 in. If the difference between measurement is more than the factory specification, loosen the lock nut of the left side. Adjust the cutting height fine turning bolts so that the difference between measurement is less than the factory specification. Then lock the nut.

Adjusting cutting height

To reduce the stepped difference in cutting height when mowing rolling terrain, follow the procedure below. To set the cutting height, move the hydraulic control lever rearward to raise the mower to the highest position. Turn the cutting height control dial to adjust height. Set the anti-scalp roller's height as shown to keep clearance between rollers and ground. Clearance between rollers and ground - 6.0 to 13 mm / 0.25 to 0.50 in. Lower the mower deck by moving the hydraulic control lever forward. Use the higher settings for mowing in a rough area or when mowing tall grass. Lower settings should be used only for smooth lawns where short grass is desired. To set the cutting height, move the hydraulic control lever rearward to raise the mower to the highest position. Turn the cutting height control dial to adjust height. Set the anti-scalp roller's position to have the same cutting height.

Kubota BX23, BX23S Tractor - Mower blade

Checking mower blade

Check the cutting edge of mower blade. Sharpen the cutting edges. To sharpen the mower blades by yourself, clamp the mower blade securely in a vise and use a large mill file along the original bevel. To balance the mower blade, place a small rod through the center hole and check to see if the blade balance evenly. File heavy side of the blade until it balance out even. Replace the mower blades. Removing ramps and belt covers RCK54-26BX and RCK60-26BX - Remove left and right ramp bracket pins. Remove left and right ramps. Remove the left and right belt covers.

Removing mower blades

To remove the blade securely, wedge a block of wood between one blade and the mower deck in such position that it will hold the blade safely while loosing or tightening the blade screw. Turn over the mower. Remove the blade mounting bolt, lock washer, cup washers, mower blade and spindle guard from the spindle holder. Install the blade in position together with the dust cover and the cup washers. Tighten them up with the bolt. Blade mounting bolt - 103 to 117 Nm / 76.0 to 86.7 lbf-ft. Removing blade boss - Remove the external snap ring. Remove the blade boss.

Removing outer pulley and blade shaft

Remove the outer pulley mounting nut, and remove the outer pulley. Remove the outer pulley holder mounting nut, and remove the outer pulley holder. Remove the oil seal and tap out the blade shaft with the ball bearing, being careful not to damage the grease fitting. Remove the ball bearing, and collar from the blade shaft. Remove the ball bearing, and oil seal.

Gear box and mower belt

Removing gear box and mower belt

Turn over the Kubota RCK54, RCK60 Mower Deck. Remove the mower belt from the tension pulley. Remove the left and right gear box mounting screws and remove the gear box from the mower deck. Gear box mounting screw - 78 to 90 Nm / 58 to 66 lbf-ft. Disassembling gear box - Remove the drain plug, and drain the gear box oil. Remove the center pulley with a puller, and remove the feather key on the bevel gear shaft. Remove the gear box cap. Remove the oil seal, internal snap ring and shim. Tap out the pinion shaft with the ball bearing, and remove the bevel gear. Remove the ball bearing and shims (if installed). Remove the external snap ring, and draw out the bevel gear shaft. Remove the bevel gear, ball bearing, shim and oil seal.

Checking mower belt

Check to see the mower belt. Replace the mower belt with a new one, if there is found surface split at more than three positions. After setting the gear box bracket mounting screws on the deck without tightening, then mount the other screws on the gear box. And finally tighten them. Dismount the mower from Kubota BX23, BX23S tractor. Remove the left and right ramp brackets. Remove the left and right hand belt cover from the mower deck. Clean around the gear box. Remove the gear box bracket (right) which mounts the gear box to the mower deck. Remove the mower belt from the tension pulley. Slip the mower belt over the top of the gear box. To install a new belt, reverse the above procedure. Gear box bracket mounting bolt and nut - 78 to 90 Nm / 58 to 66 lbf-ft. Gear box mounting screw - 78 to 90 Nm / 58 to 66 lbf-ft.

Removing center pulley holder

Remove the center pulley holder bolt / center pulley nut. Remove the upper oil seal and lower oil seal. Remove the internal snap ring and ball bearing. When reassembling the center pulley holder, gear box and gear box bracket, tighten the bolts and nuts in the order as below, to prevent the incline the gear box. Tighten the reamer screw to the gear box first, then tighten the reamer bolts and nut to the center pulley holder with specified torque. Tighten the gear box screws to the gear box and then tighten the center pulley holder bolts and nut with specified torque. Replace the oil seals with new ones. Install the reamer screw / reamer bolt at their original positions as shown in the figure. Be sure to fix the O-rings to the original position. Center pulley holder bolt and nut 78 to 90 Nm / 58 to 66 lbf-ft.

Kubota BX23, BX23S Tractor - Mower Servicing

Adjusting turning torque of pinion shaft - Set the blade screw for the blade shaft to measure the turning torque. Turn the blade screw clockwise with torque wrench and measure the turning torque. Turning torque - Less than / 0.7 Nm 0.52 lbf-ft. Thickness of adjusting shims - 0.2 mm 0.0079 in. / 0.3 mm 0.0118 in. Thickness of adjusting shims - 0.2 mm 0.0079 in. / 0.3 mm 0.0118 in. Adjusting backlash between bevel gears - Remove the gear box cap. Place the plastigauges or wire of solder the bevel gear on the input shaft. Turn the input shaft. Remove the plastigauges or wire of solder, and measure the thickness with the gauge or an outside micrometer.