Disassembly/Assembly

DISASSEMBLY

1. Secure vacuum pump in holding fixture No. 115589142100 or equivalent, with fixture spindle completely backed out. Casting seam on vacuum pump must be centered between the two forward screws of holding fixture.
2. Turn holding fixture spindle up to stop to preload diaphragm.
3. Remove vacuum pump closing cover attaching screws and the cover.
4. Remove compression springs and plate valves from pump housing.
5. Mark relationship between pump cover and housing for assembly reference, then remove cover attaching screws and the cover.
6. Remove diaphragm attaching screw from rod, then the diaphragm and two discs.
7. Back off holding fixture spindle to relieve spring pressure, then remove vacuum pump from holding fixture.
8. Remove upper spring retainer and two compression springs from diaphragm rod.
9. Remove rocker arm shaft plug from housing, then remove shaft, rocker arm and diaphragm rod from pump housing.
10. Remove diaphragm rod guide bushing, then the lower spring retainer.

ASSEMBLY

1. Position lower spring retainer on diaphragm rod, then press on guide bushing.
2. Secure diaphragm rod to rocker arm with bearing bolt, then install locking rings.
3. Install upper spring retainer and two compression springs into pump housing.
4. Position diaphragm rod with lower spring retainer, then install rocker arm and mount shaft.
5. Install rocker arm shaft into housing.
6. Secure vacuum pump in holding fixture and preload diaphragm rod by turning holding fixture spindle to stop so dimension ``a,'' equals approximately 1.02 inch (26mm).
7. Remove all grease from threads in diaphragm rod.
8. Position large diaphragm plate, with both blind holes downward, on diaphragm rod.
9. Install diaphragm, with raised or lettered portion facing up, then the smaller diaphragm plate.
10. Apply suitable locking compound to diaphragm rod screw, then install screw with copper sealing ring. Torque screw to 7 ft. lbs. while holding diaphragm with a suitable tool.
11. Install pump cover, referring to marks made during disassembly, and torque attaching screws to 4 ft. lbs.
12. Install seals and plate valves into valve seats.
13. Install compression springs, then the pump closing cover with new gasket.