GMC T Series 1994 Repair Manual page 292

16. DIAPHRAGM, POWER PISTON
17. PLATE, PRIMARY SUPPORT
19. DIVIDER, HOUSING
20. DIAPHRAGM, SECONDARY
41. PISTON, POWER
Figure 11— Installing the Primary Diaphragm
7. Reaction piston (23) and reaction disc (22) in reac­
tion body (25).
8. Reaction body (25) in power piston.
9. Secondary diaphragm (20) on secondary support
plate (21).
10. Lubricate inside diameter of secondary diaphragm
(20) lip with a thin layer of Delco Silicone Lube
(GM P/N 18010909) or equivalent.
11. Secondary diaphragm (20) and support plate (21)
over power piston assembly (41) and pushrod (32)
(figure 9).
• Use J 28458 as a guide to protect power pis­
ton.
12. Secondary piston bearing (18) into housing divider
(19) with flat surface of the bearing on the same
side as six raised lugs on divider.
13. Lubricate inside diameter of secondary piston bear­
ing (18) with a thin layer of Delco Silicone Lube
(GM P/N 18010909) or equivalent.
14. Secondary piston bearing (18) and housing divider
(19) over the power piston assembly (41) (figure
10
).
• Use J 28458 as a guide.
15. Lubricate inside diameter of primary diaphragm
(16) lip with a thin layer of Delco Silicone Lube
(GM P/N 18010909) or equivalent.
16. Primary diaphragm (16) into the primary support
plate (17) (figure 11).
• Fold primary diaphragm (16) up and away from
primary support plate (17).
13. RETAINER, DIAPHRAGM
V2783
17. Primary diaphragm (16) and support plate (17) over
power piston assembly (41).
• Unfold primary diaphragm (16) back in position
and pull outside edge of diaphragm over formed
flange of housing divider (19).
• Make sure the beads on secondary diaphragm
(20) are seated evenly around the complete cir­
cumference.
18. New diaphragm retainer (15) and seat using
J 28458 (figure 12).
• Do not reuse original retainer.
19. Silencer (14), reaction retainer (13), reaction body
retainer (24), and piston rod (12).
20. Lubricate inside and outside diameters of primary
piston bearing (8) with Delco Silicone Lube (GM
P/N 18010909) or equivalent.
21. Primary piston bearing (8) in rear housing (9).
22. Power piston group (38) in rear housing (9).
23. Return spring (11).
24. Lock front and rear housings (9 and 10) using the
following steps:
A. Set assembled rear housing group in assembly
tool J 23456.
B. Align the scribe marks on housings (9 and 10).
C. Tighten the fixture hand screw just enough to
allow for housing rotation (figure 1).