CHAMPION USN10 - Manual (Page 60)

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PART 5: BASIC SERVICE
5.3 Component Repair and Replacement (Cont.)
5.3.14 Pump Seal Replacement
Refer to Fig. 6.8, Replacement Parts, for a detailed drawing of the pump/motor assembly.
Perform the steps listed below to replace a pump seal.
1. Disconnect the power to the machine at the main breaker panel or fuse box.
2. Drain the machine.
3. Remove the front and side panels (if applicable).
4. Remove drain plug on the pump volute and drain the pump.
5. Remove the pump hoses.
6. Disconnect the wires to the motor at the motor junction box.
7. Unbolt motor from machine base and remove the pump/motor assembly.
8. Remove bolts on volute and carefully remove from the pump flange.
9. Remove the impeller retaining bolt and nut from center of impeller.
10. Lock the motor shaft with a wrench or pliers. The back of motor shaft is square.
11. Turn the impeller counterclockwise to remove from shaft (right hand threads).
12. Remove the old seal and discard.
13. Check seal seat in the pump flange and clean thoroughly.
14. Press rubber seal/ceramic portion of seal assembly into the pump flange. Use a water
soluble lubricant. Be careful to keep the ceramic clean.
15. Install the rotating part of the seal on the shaft with the graphite surface toward the ceramic.
Use a water soluble lubricant on the rubber seal part only (not the graphite).
16. Reinstall impeller, and new flange gaskets. Reinstall bolts. Reinstall drain plug.
17. Reinstall the pump/motor assembly and reconnect the pump hoses.
18. Fill the dishwasher with water.
19. Check motor rotation by bump starting motor.
Correct motor shaft rotation is clockwise when viewing motor from the rear.
20. Test run and check for leaks.
5.3.15 Door Safety Switch
Refer to Fig. 6.1 Replacement parts item numbers 9 and 10. The door safety switch assembly
consists of a magnet on the inside wall of the tank and a magnetic reed switch mounted to the
bottom of the tank. Studs are welded on the bottom of the tank and nuts hold the switch in place.
The magnet is mounted to a bracket that pivots causing a break in the connection with the switch
when the door is opened or closed. The magnet is enclosed by a stainless steel housing. The door
safety switch prevents the machine from operating when the door is opened during operation.
To check the door safety switch: Disconnect the power to the machine at the main breaker
panel or fuse box. Inspect the inside of the machine to make sure that the magnet and bracket is
in place and secure. Remove the screws on the front panel of the machine. Swing the panel open
and look for the switch located to the right side of the panel underneath the edge of the tank.
Remove the door switch cover and disconnect the reed switch leads. Make sure that the door is
fully closed. Connect the door switch harness wires together. Turn the power on and check to see
if the machine runs normally. If machine operates, turn off power and replace the door safety
switch. Do not leave the door switch bypassed for any other reason than to test.
To replace the door safety switch: Disconnect the power to the machine at the main breaker
panel or fuse box. . Note the orientation of the reed switch. Mark the wires and disconnect.
Remove the (2) retaining nuts holding the switch. Install the new switch and reassemble in the
reverse order. Restore power to the machine and check for proper operation.