Intermediate Cover

Remove worm with intermediate cover and piston from gear housing. Unscrew worm from piston.
CAUTION: Do not lose balls.

Remove intermediate cover, then remove recirculating tube. Inspect needle roller cage, bearing washer, slotted ring, "O" ring, and sealing ring.

NOTE: The shim washer is required for adjusting position of slotted ring.

Inspect cover sealing rings (four used).

Fig 1: Intermediate Cover Seal Locations
Courtesy of BMW OF NORTH AMERICA, INC.

Fig 2: Removing Worm From Piston
Courtesy of BMW OF NORTH AMERICA, INC.
Temporarily assemble valve housing without ring seal, worm head without Teflon sealing rings, intermediate cover without "O" ring and slotted ring with ball bearing, needle roller cage and bearing washer to valve housing, and tighten screws evenly. Install torque wrench and check preload of worm bearing. Replace bearing washer if necessary with one of correct thickness to obtain torque specification shown in table at end of this article.
Check prestressing of Teflon ring in intermediate cap as follows: Place bearing disc and retainer ring in intermediate cap. Install "O" ring and Teflon ring (.067" (1.7 mm) thick) into groove, and install on worm shaft. Install a torque wrench and check preload with shaft in vertical position. Replace Teflon ring if necessary with one of correct thickness to obtain torque specification shown in table at end of this article.

Fig 3: Intermediate Cover
Courtesy of BMW OF NORTH AMERICA, INC.

Fig 4: Assembling Worm Bearings
Courtesy of BMW OF NORTH AMERICA, INC.