2. Loosen the gear shaft adjusting screw locknut and remove the gear cover bolts (photo).
16.2 Steering gear parts
1, 10. Locknut; 2, 6 Oil seal; 3. Adjusting nut; 4. Ball nut and reducer drive shaft; 5. Spring washer; 7. Housing; 8. Bipod shaft; 9. Adjusting screw; 11. Cork; 12. Lid; 13. Gasket; 14. Regulator
3. Loosen the adjusting screw by turning it clockwise and remove the cover.
4. Remove the bipod shaft and remove the adjusting screw.
5. Using a special wrench, unscrew the adjusting nut (photo).
16.5 Loosening the gearbox adjusting nut
6. Remove the drive shaft of the gearbox along with the adjusting nut (photo).
16.6 Removing the gearbox input shaft with adjusting nut
Attention! Do not allow the balls to move towards the ends of the worm thread. Otherwise, the worm part of the shaft will be damaged. In case of wear or damage, the ball nut and the worm must be replaced.
7. The needle bearings of the bipod shaft must not be removed. If the bearings are worn, replace the entire gearbox.
8. Turn out an adjusting nut and knock down an epiploon from a nut.
9. Pry and remove the oil seal from the gearbox housing.
10. Wash all parts.
11. Inspect the teeth on the bipod shaft for cracks or burrs.
12. Check the condition of the splines of the bipod shaft.
13. Check the condition of the threads on the drive shaft for cracks, burrs and other damage. Check the freedom of rotation of the ball nut on the worm. Check the freedom of movement of the balls, gradually turning the shaft into a vertical position, the balls should roll under their own weight. Otherwise, replace the drive shaft.
Attention! When checking, do not allow the ball to roll into the very end of the tooth of the worm thread.
14. Check the freedom of rotation of the gearbox bearings. If seizing, replace the bearing assembly with the outer race.
15. Lubricate all parts before assembly. Install the new oil seals with the lettered side facing out. Apply grease to the seals.
16. Install a new oil seal on the adjusting nut.
17. Install the drive shaft assembly with the nut into the gearbox. Screw the nut onto the threads in the gearbox.
18. Place a preload in the gearbox input shaft bearings (photo). To do this, gradually tighten the adjusting nut until the moment of resistance to turning the shaft is equal to that specified in the Technical data.
16.18 Creating a preload in the bearings of the steering gear input shaft
The torque is measured with a torque wrench with a scale of a few Nm after the drive shaft has been rotated in both directions by a few revolutions. To improve the engagement of the splines with the key, insert a piece of plastic card into the key head.
19. Lubricate the ring locknut with a fixing compound and tighten the adjusting nut with it, preventing the adjusting nut from turning. Check the bearing preload again.
20. Install an adjusting screw in the T-shaped cutout of the bipod shaft and check the axial clearance of the screw in the cutout (photo). Compensate for this gap to the norm by selecting an adjusting washer according to the thickness (see technical data).
16.20 Checking the axial clearance of the bipod shaft
1. Adjusting washer; 2. Backlash shaft bipod; 3. Towards the gearbox cover
21. Install a new oil seal in the shank of the steering gear housing.
22. Turning the adjusting screw counterclockwise, install the housing cover on the shaft, tighten the locknut (photo).
16.22 Before installing the cover on the shaft, tighten the screw by turning it counterclockwise
23. Install the gasket on the cover, lubricating both sides with sealant.
24. Turn the drive shaft by hand and set the ball nut to the middle position. Install the bipod shaft with the propeller. Make sure the center tooth on the bipod shaft engages with the center groove of the ball nut. When performing this procedure, do not damage the lips of the gland.
25. Torque tighten the cover bolts.
26. Fill the gearbox with oil and tighten the plug.
27. Preload the bipod shaft bearings by turning the adjusting screw (photo). The resistance to rotation of the bipod shaft must correspond to that specified in the Technical data. The moment is checked with the position of the bipod shaft in the driving position in a straight line.
16.27 Check the moment of resistance to rotation of the bipod shaft by gradually turning the adjusting screw
1. Screwdriver
28. Tighten the locknut and check the tightness again.