GMC 1976 ZEO 6083 Maintenance Manual page 801

TYPE 1 WATER PUMP OVERHAUL
(FIGURE 14)
VALVES REPLACEMENT
1 . Turn off power to pump .
2 . If system is filled with water, open a faucet to
relieve pressure . Close intake and discharge lines
near pump. Remove pump from vehicle.
3. Remove motor and four tie down screws (fig-
ure 15).
4. Expose valves by lifting jack shaft and attached
diaphragm assembly from pump base . (figure 16) .
5. Lift valves from pockets. Clean all foreign
materials from valves and seats (figure 17) .
6. Reinstall valves into same pockets, being sure
rubber valve with small hole is UP on intake and
rubber valve without the small hole is DOWN on
discharge. NOTE : Do not use valve with small hole
in rubber on discharge side of pump .
7. When reassembling, adjust belt tension to 1/8"
play .
DIAPHRAGM
1 . Turn off power to pump .
2. If system is filled with water, open a faucet to
Figure 1 5-Opening Water Pump
LIVING AREA WATER SYSTEM 24 .1- 11
Figure 16-Water Pump Valves
relieve pressure . Close intake and discharge lines
near pump. Remove pump from vehicle.
3. Remove motor and four tie down screws then
lift jack shaft and attached diaphragm assembly from
pump base .
4. Expose diaphragm by removing two dia-
phragm retain screws and detaching.
Figure 17-Water Pump Valve Removed