105683-0290 ZEXEL 9 420 616 063 BOSCH AUTOM. ADVANCE MECHANISM 9420616063 1056830290 225003490a

Operation
At all speeds the rotor blades are kept in contact with the bore of the body by centrifugal force, assisted by the hydraulic action of the oil beneath the blades. When the rotor turns, the spaces between the blades vary because of the eccentric mounting of the rotor in the exhauster body. As a blade passes the inlet port, the space between it and the following blade is increasing and air is drawn from the vacuum reservoir. This air is then compressed and expelled, with the lubricating oil, through the outlet port to the engine timing case.Periodic Inspections and Preventive Maintenance
Every 5,000 miles (7,500 km) or 250 Hours
Check the vacuum lines and fittings. (Vacuum leakage may occur through the line, or reservoir mounted non-return valve if the valve seat is dirty or pitted). Examine the exhauster for evidence of oil leakage, particularly at end cover joints, and at shaft oil seal.Check the oil supply line for leaks at fittings and connections.Check the mounting and end cover nuts and bolts for tightness.Every 60,000 Miles (90,000 km) or 2,500 Hours
Remove and dismantle exhauster, thoroughly clean all parts and inspect for wear and damage. Repair or replace the exhauster with a Factory Replacement Unit.Removal
Disconnect oil and vacuum pipes at the exhauster and plug ends to prevent the entry of foreign matter.
Q2 1. Distance Piece2. ExhausterUndo the four nuts that secure the exhauster to the timing case, and withdraw the unit complete with its driving gear, from the studs (Fig. Q.2).Dismantling
Remove the two half-round thrust plates which locate the drive gear on the front of exhauster shaft.Remove drive gear.Mark the end covers in relation to the body to correct location on re-assembly.Unscrew four setscrews and remove rear end cover with rubber sealing ring.Mark the blades in relation to the rotor.Withdraw the rotor and fibre blades from the body.Unscrew four socket headed screws, and remove drive end cover, with joint or rubber ring.Remove rear end cover circlip, blanking disc, and rubber oil seal ring, if fitted. Further dismantling of the rotor assembly need be undertaken only if, after inspection, it is found necessary to renew the bearing or shaft collar.Cleaning and Inspection Cleaning
Wash the roller bearing, where fitted, in thin flushing oil or white spirit and blow dry with compressed air. Spinning the bearing with compressed air should be avoided, otherwise damage to the rollers and race will occur.Wash the remaining components in cleaning solvent, and clear the rotor and drive end cover oilways with compressed air.Inspection of Parts
Examine the roller bearings, where fitted, for discolouration, wear, pitting and cracked races. Rotate slowly to examine for roughness. To renew, see "Overhaul" Section. Premature failure may have been caused by shortage of oil.Examine plain bearing(s) for excessive wear. To renew, see "Overhaul" Section.Inspect rotor and shaft for cracks and damage, and the shaft seal collar for wear. To renew collar, see "Overhaul" Section.Check fit of blades in rotor slots, replace any worn or damaged blades.Examine the seal(s) carefully to see that the sealing edge