VALVE SERVICE
55
Rev E
To install the top plate:
1. Position the top plate on top of the valve and over the valve discs.
2. Insert a screw at one of the corner positions.
A. Drop screw of same size and thread into the hole.
B. Use a phillips screwdriver and lightly rotate the screw backwards
(counterclockwise).
C. When the thread of the screw and the thread of the hole match, the
screw will “click” and slightly drop down.
D. The threads are lined up. Lightly rotate the screw to tighten and engage
threads.
E. Once the threads have engaged the screw can be tightened. Minimal
resistance will be present as the screw is turned in. Resistance
indicates new threads are being formed. Back the screw out and
rematch the threads.
3. Turn the screw in but do not tighten.
4. Place a second screw into the hole diagonally opposite the first screw and
turn in but do not tighten.
5. Insert another screw into one of the remaining corners and turn it in.
6. The fourth screw goes into the hole diagonally opposite. Turn it in.
7. Put the remaining screws in following the same criss-cross pattern
working from the ends toward the center. When all the screws are in place
they can be tightened down.
8. Start at the corner of the screw pattern and tighten that screw. Work the
same pattern from the ends toward center and
criss-crossing as each screw is tightened. Check that each valve disc
moves smoothly before replacing the spring and camshaft.
9. Replace spring.
10. Replace camshaft and motor.
11. Replace controller and wiring harnesses.
NOTE:
All valve discs should be in position. Use the same screws that
were removed to reassemble the top plate.
WARNING:
Follow the procedure to engage the screws with the existing
threads. If the same threads are not used, the holding power of the screw is
lost. Under pressure the valve can leak. Screws that have the same
diameter but have different threads should not be used.
WARNING:
This procedure for reinserting screws must be followed to
ensure proper holding strength of the screws.
1 5 9 13 17
15 11 7 3
4 8 12 16 18 14 10 6 2