SERVICE MANUAL UPDATE-SEC. 1B HEATER CORE AND A/C EVAPORATOR

SUBJECT: SECTION IB HEATER CORE AND A/C EVAPORATOR (FRONT)

VEHICLES AFFECTED: 1990-93 "U" VAN OLDSMOBILE SILHOUETTE

Bulletin revised to correct text as follows: Under heading "Heater Core and A/C Evaporator (Remove and Disconnect) - first line revised and Step 24 has been changed. Heading "Figure 17 A/C Evaporator - Steps 25 and 42 have been revised. Art work remains the same.

APPLICATION:

----------- 1990-93 Oldsmobile Silhouette

This bulletin serves to cancel and supersede the heater core and cover and A/C front evaporator core procedures found in Section 1 B of the 1990-93 Oldsmobile Silhouette Service Manuals. Use this procedure whenever service of the front heater core and/or A/C evaporator if necessary.

Heater Core and A/C Evaporator (Front) -------------------------------------- Remove or Disconnect -------------------- o IF REPLACING A/C EVAPORATOR - Recover refrigerant. Refer to Section 1 B. Drain engine coolant. Refer to SECTION 6B.

1. Two screws (838) attaching RH windshield wiper transmission (837) arm to windshield wiper frame (836) (Figure 1).

Figure 1 Windshield Wiper Frame and Transmission

o Move RH windshield wiper transmission arm aside to gain access to heater hoses.

2. Clamp and heater outlet hose (105) from heater core (123)

3. (Figure 2).

Figure 2 Heater inlet and Outlet Hoses

3. Clamp and heater inlet hose (104) from heater core (123) (Figure 2).

4. RH I/P sound insulator panel push-in retainers (803), screw (806) and nut (805) from stud (Figure 3).

Figure 3 RH I/P Sound Insulator Panel

o Carefully pull RH I/P sound insulator panel (802) away from I/P (Figure 3).

5. Floor (courtesy) lamp (804) from RH I/P sound insulator panel (802) (Figure 3).

6. RH I/P sound insulator panel (802) from vehicle (Figure 3). Open I/P compartment door.

7. Three screws (809) from bottom of I/P compartment insert (808) (Figure 4).

Figure 4 I/P Compartment

8. Three upper I/P compartment screws (809) with two bumpers (81 0) (Figure 4).

9. Electrical connector from I/P compartment lamp and switch assembly.

10. I/P compartment (with door) (808) from I/P (Figure 4).

11. Bolt (113) and nut (115) from I/P lower brace (114) (early model vehicles) (Figure 5).

Figure 5 I/P Lower Brace

12. I/P lower brace (114) from I/P (early model vehicles) (Figure 5).

13. Two screws (839) retaining I/P lower extension housing (801) to I/P lower extension support brackets (840) (1993 vehicles only) (Figure 6).

Figure 6 I/P Lower Extension Housing Attachments

14. RH I/P outer support-to-I/P lower trim pad attaching bolt (812) (Figure 7). Position wedge between RH I/P outer support (811) and I/P lower trim pad (807) (Figure 7). Wedge will provide sufficient clearance for removal and installation of heater core.

Figure 7 RH I/P Outer Support (Typical)

15. Heater and A/C control vacuum harness (117) from vacuum/electric solenoid (116) (Figure 8).

Figure 8 Heater Core Cover and Temperature Case

16. Two screws retaining vacuum/electric solenoid (116) (Figure 8).

17. Vacuum/electric solenoid (116) from heater core cover (112) (Figure 8).

18. Six screws (147) and two clips (122) from heater core cover (112) (Figure 9).

19. Heater core cover (112) and seal (118) from temperature case (126) (Figure 9).

20. Heater core lower bracket retaining screw (late model vehicles).

21. Heater core lower bracket (late model vehicles).

22. LH retaining screw from heater core upper bracket (late model vehicles). Loosen RH retaining screw from heater core upper bracket (late model vehicles). Adjust heater core upper bracket to allow heater core removal (late model vehicles).

23. Heater core inlet/outlet tubes from tube/case seal (120) (Figure 9).

Figure 9 Heater Core and Related Components

24. Heater core (123) and seal (119) from temperature case (126) (Figure 9).

STOP HERE - If only replacing heater core. See "Inspect" steps 1, 2 and 3 and "Install or Connect" steps 26 through end of procedure.

25. Windshield wiper and washer switch retaining screw (845) (Figure 10).

26. Windshield wiper and washer switch (846) from I/P cluster trim plate (843) (Figure 10). Disconnect electrical connector from switch.

27. Headlamp switch retaining screw (845) (Figure 10).

28. Headlamp switch (817) from I/P cluster trim plate (843) (Figure 10). Disconnect electrical connector from switch.

Figure 10 I/P Cluster Trim Plate

29. Two screws (849) attaching I/P cluster trim plate (843) to LH and RH instrument cluster retainers (847 and 848) (Figure 11).

30. Twos crews (850) attaching I/P cluster trim plate (843) to I/P trim pad (818) (Figure 11).

Figure 11 I/P Cluster Trim Plate Attachments

31. LH and RH side window defogger outlet grilles (829) from I/P trim pad (818) (Figure 12).

Figure 12 Side Window Defogger Outlet Grilles

32. Screws (830) behind side window defogger outlet grilles (829) (one on each side of I/P trim pad) (Figure 12).

33. Two screws (832) (above I/P compartment area) retaining I/P trim pad (818) to I/P lower trim pad (807) (Figure 13).

Figure 13 I/P Trim Pad Attachments

34. I/P trim pad (818) from I/P lower trim pad (807).

35. Electrical connector and harness from temperature valve actuator (109) (Figure 14).

36. Two screws from temperature valve actuator (109) and actuator from temperature case (126) (Figure 14).

Figure 14 Temperature Valve Actuator

37. Two lower screws (130) from temperature case (Figure 15).

38. One upper LH screw (130), one upper RH screw (130), temperature case (126) and gasket (129) from blower and air inlet case (128) (Figure 15). Removal of upper RH temperature case screw (130) may require partial removal of adhesive insulator patch.

Figure 15 Temperature Case

39. A/C accumulator hose (133) from A/C evaporator (144) (Figure 16).

40. A/C evaporator hose (136) from A/C evaporator (144) (Figure 16).

Figure 16 Blower and Air Inlet Case

41. Four screws (132) retaining auxiliary A/C evaporator and blower case (131) to blower and air inlet case (128) (Figure 16).

42. Windshield defogger nozzle duct (127) (Figure 14).

43. A/C evaporator (144) inlet/outlet tubes from drain grommet and A/C evaporator (with case) from blower and air inlet case (128) (Figure 17).

44. Tube and drain seal (140) from A/C evaporator (144) (Figure 17).

45. One screw (137) retaining evaporator tube clamp (138) (Figure 17).

Figure 17 A/C Evaporator

46. Four A/C evaporator case clips (143) (Figure 17).

0 Separate upper and lower auxiliary A/C evaporator and blower case halves (131) (Figure 17).

47. Six stake retainers (142) and filter (141) from A/C evaporator (Figure 17).

48. Evaporator core mounting spacers (139) (Figure 17).

49. Evaporator core seal (145) (Figure 17).

INSPECT

1. Heater core (123) for signs of damage, leakage or internal restriction. Repair or replace as necessary.

2. Tube/case seal (120) for damage or deformation. Replace as necessary.

3. Heater core seals (118 and 119) for damage or deformation. Replace as necessary.

4. A/C evaporator (144) for signs of damage, leakage or internal restriction. Replace as necessary.

5. Evaporator core seal (145) for damage or deformation. Replace as necessary.

6. Tube and drain seal (140) for damage or deformation. Replace as necessary.

7. Drain grommet for damage or deformation. Replace as necessary.

INSTALL OR CONNECT

1. Evaporator core seal (145) (Figure 17).

2. New evaporator core mounting spacers (139) (Figure 17).

3. New filter (141) to A/C evaporator (144) with six stake

4. retainers (142) (Figure 17).

5. A/C evaporator (144) into upper and lower auxiliary A/C

6. evaporator and blower case halves (131) (Figure 17).

7. Upper and lower auxiliary A/C evaporator and blower case

8. halves (131) with four A/C evaporator case clips (143)

9. (Figure 17).

10. Evaporator tube clamp (138) with screw (137) (Figure 17).

Tighten

o Evaporator tube clamp screw (137) to 7 N.m (62 lb.in.).

7. Tube and drain seal (140) to A/C evaporator (144) (Figure 17).

8. A/C evaporator inlet/outlet tubes to drain grommet and A/C

9. evaporator (with case) (144/131) into blower and air inlet

10. case (128) (Figure 15).

11. Windshield defogger nozzle duct (127) (Figure 14).

12. Four screws (132) retaining auxiliary A/C evaporator and

13. blower case (131) to blower and air inlet case (128) (Figure 16).

Tighten

o Auxiliary A/C evaporator and blower case screws (132) to 10 N.m (89 lb.in.).

Important: Lubricate new 0-ring seals prior to installation with 526 viscosity mineral refrigerant oil only. Do not use PAG oil to lubricate 0-ring seals.

11. A/C evaporator hose (136) to A/C evaporator (144) with new 0-ring seal (135) (Figure 16).

12. A/C accumulator hose (133) to A/C evaporator (144) with new 0-ring seal (134) (Figure 16).

13. Temperature case (126) and gasket (129) to blower and air inlet ease with two upper screws (130) (Figure 15).

Tighten

o Upper temperature case-to-blower and air inlet case screws (130) to 7 N.m (62 lb.in.).

14. Two lower screws (130) to temperature case (Figure 15).

Tighten

o Lower temperature case-to-blower and air inlet case screws (130) to 7 N.m (62 lb.in.).

15. Temperature valve actuator (109) to temperature case (126) with two screws (Figure 14).

Tighten

o Temperature valve actuator screws to 8 N.m (71 lb.in.).

16. Electrical connector and harness to temperature valve actuator (109) (Figure 14).

o Position I/P trim pad (818) onto I/P lower trim pad (807).

17. Two screws (832) (above I/P compartment area) attaching I/P trim pad (818) to I/P lower trim pad (807) (Figure 13).

Tighten

o I/P trim pad-to-I/P lower trim pad attaching screws (832) to 2 N.m (18 lb.in.).

18. Screws (830) behind side window defogger outlet grilles (829) (one on each side of I/P trim pad) (Figure 12).

Tighten

o I/P trim pad-to-I/P lower trim pad attaching screws (830) to 3 N.m (27 lb.in.).

19. LH and RH side window defogger outlet grilles (829) to I/P 20. Two screws (849) retaining I/P cluster trim plate (843) to LH and RH instrument cluster retainers (847 and 848) (Figure 11).

20. Two screws (850) retaining I/P cluster trim plate (843) to I/P trim pad (818) (Figure 11).

Tighten

o I/P cluster trim plate retaining screws to 2 N.m (18 lb.in.).

22. Electrical connector to headlamp switch (817).

23. Headlamp switch (817) to I/P cluster trim plate (843) and secure with retaining screw (845) (Figure 1 0).

24. Electrical connector to windshield wiper and washer switch (846).

25. Windshield wiper and washer switch (846) to I/P cluster trim plate (843) and secure with retaining screw (845) (Figure 10).

o START HERE - If only replacing heater core.

26. Heater core inlet/outlet tubes into tube/case seal (120) and heater core (123) and seal (119) into temperature case (126) (adjusting heater core upper bracket if equipped) (Figure 9).

27. LH retaining screw to heater core upper bracket - do not fully tighten (late model vehicles).

28. Heater core lower bracket with retaining screw (late model vehicles).

0 Adjust positioning of heater core in temperature case to prevent any movement.

Tighten

0 Heater core bracket retaining screws to 3 N.m (27 lb. in.).

29. Heater core cover (112) and seal (118) to temperature case (126) with six screws (147) and two clips (122) (Figure 9).

Tighten

o Heater core cover screws (147) to 7 N.m (62 lb.in.).

30. Vacuum/electric solenoid (116) to heater core cover (112) with two screws (Figure 8).

Tighten

o Vacuum/electric solenoid screws to 7 N.m (62 lb.in.).

31. Heater and A/C control vacuum harness (117) to vacuum/electric solenoid (116) (Figure 8).

0 Remove wedge from between RH I/P outer support (811) and I/P lower trim pad (807) (Figure 7).

32. RH I/P outer support-to-I/P lower trim pad attaching bolt (812) (Figure 7).

Tighten

o RH I/P outer support-to-I/P lower trim pad attaching bolt (812) to 10 N.m (89 lb.in.).

33. Two screws (839) retaining I/P lower extension housing (801) to I/P lower extension support brackets (840) (Figure 6).

Tighten

o I/P lower extension housing-to-I/P lower extension support bracket screws to 3 N.m (27 lb.in.).

34. I/P lower brace (114) with nut (115) and bolt (113) (early model vehicles) (Figure 5).

Tighten

0 I/P lower brace nut (115) to 10 N.m (89 lb.in.).

0 I/P lower brace bolt (113) to 8 N.m (71 lb.in.).

35. Electrical connector to I/P compartment lamp and switch assembly while positioning I/P compartment into I/P (with door open).

36. Three upper I/P compartment screws (809) with two bumpers (810) (Figure 4).

37. Three lower I/P compartment screws (809) (Figure 4).

Tighten

0 I/P compartment screws (809) to 3 N.m (27 lb.in.).

0 Close I/P compartment door.

38. Floor (courtesy) lamp (804) to RH I/P sound insulator panel (802) while positioning panel into, I/P (Figure 3).

39. RH I/P sound insulator panel screw (806), nut (805) and push- in retainers (803) (Figure 3).

Tighten

o RH I/P sound insulator panel attaching screw (806) to 3 N.m (27 lb.in.).

40. Heater inlet hose (104) to heater core (123) and secure with clamp (Figure 2).

41. Heater outlet hose (105) to heater core (123) and secure with clamp (Figure 2).

42. Two screws (838) attaching RH windshield wiper transmission (837) arm to windshield wiper frame (836) (Figure 1).

Tighten

0 RH windshield wiper transmission arm-to-windshield wiper frame screws (838) to 7 N.m (62 lb.in.).

0 Refill engine coolant. Refer to SECTION 6B.

0 IF A/C EVAPORATOR HAS BEEN REPLACED - Recharge refrigerant. Refer to Section 1 B.

WARRANTY INFORMATION

Heater Core Labour Operations: D2800/D2802/D2820/D2322

New Labour Time: 1.2 Hrs.

A/C Evaporator Labour Operation: D3320

New Labour Time: 2.7 Hrs.

General Motors bulletins are intended for use by professional technicians, not a "do-it-yourselfer". They are written to inform those technicians of conditions that may occur on some vehicles, or to provide information that could assist in the proper service of a vehicle. Properly trained technicians have the equipment, tools, safety instructions and know-how to do a job properly and safely. If a condition is described, do not assume that the bulletin applies to your vehicle, or that your vehicle will have that condition. See a General Motors dealer servicing your brand of General Motors vehicle for information on whether your vehicle may benefit from the information.