Service Procedure
1. Perform normal diagnostics as outlined in the Cooling System Symptom charts located in the appropriate model year Workshop Manual. Service as required.2. If not previously installed, install appropriate Coolant By-Pass Kit. Refer to the Instruction sheet included in the kit for details.
3. Install water pump on 1996-98 models only. Refer to Workshop manual, Section 03-01A for replacement details.
4. Perform the following flush and fill procedures if coolant is discolored.
FLUSH AND FILL PROCEDURE RECOMMENDED TOOLS
The tools shown in Figure 1 are referenced throughout the technical Instruction to facilitate the flush procedures. Tools should be obtained locally.
FLUSH AND FILL PROCEDURE
NOTE
POSITION THE VEHICLE ON A HOIST WHERE A GARDEN HOSE CAN BE USED AND COOLANT CAN BE DISCARDED.
WARNING
COOLANT MAY BE HOT. REMOVE COOLANT PRESSURE RELIEF CAP.
1. Raise vehicle on hoist.
2. Remove splash shield.
3. Remove Radiator draincock and completely drain and discard coolant.
4. Lower vehicle.
5. Loosen alternator brace retaining nuts and position brace away from heater return hose (Figure 2).
6. Turn Heater and Blower Switches to off.
7. Disconnect heater return hose from water pump and discard clamp.
8. FOR 96, 97 AND SOME 98 MODEL YEAR VEHICLES PROCEED WITH THE SEDIMENT AND CHEMICAL FLUSH PROCEDURES. FOR 99 MODEL YEAR, COMPETE THE CHEMICAL FLUSH PROCEDURE ONLY.
SEDIMENT FLUSH PROCEDURE
9. Disconnect upper radiator hose from thermostat housing and discard clamp.
10. Using clamping pliers, clamp off coolant by-pass hose at center of hose (Figure 3).
11. Raise and support vehicle.
12. Remove engine block core plug located next to the oil filter. On the opposite side of the engine block, there are two core plugs; remove the engine block core plug closest to the water pump.
13. Remove lower radiator support bracket that covers lower radiator hose.
14. Remove lower radiator hose from radiator and discard clamp.
15. Clean core plug bores in cylinder block with sand paper drum (Fine 150-grit 1.5" dia.). Ensure all Loctite and rust is removed from core plug bore.
16. Lower vehicle.
17. Connect garden hose to heater return hose using adapter (Figure 4).
18. Turn garden hose on full pressure.
19. Flush engine/heater core for ten (10) minutes. Water will drain out of core plug holes.
20. Disconnect garden hose from heater return hose.
21. Insert garden hose into upper radiator hose (Figure 5).
22. Flush radiator for two (2) minutes. Water will drain out of lower radiator hose connection and draincock.
23. Remove garden hose from upper radiator hose.
24. Insert garden hose into coolant recovery bottle (Figure 6).
25. Flush coolant recovery bottle for four (4) minutes. Water will drain out of lower radiator hose.
26. Remove garden hose from coolant recovery bottle. Let cooling system completely drain before proceeding to next step.
27. Remove clamping pliers from coolant by-pass hose.
28. Install new screw clamp on upper radiator hose. Connect upper radiator hose to thermostat housing and tighten clamp.
29. Raise and support vehicle.
30. Lubricate O-rings of new engine core plugs (-6C057-) with silicone dielectric grease (WA-10).
31. Install left and right bank front engine core plugs. Index dimples on the plugs to 12 o'clock position. (Figure 7).
NOTE
DO NOT OVER TORQUE.
32. Tighten core plug retaining nuts to 3.2 Nm (28 lb-in). See Figure 7. Use 1/4" drive, 8mm flex socket with a long extension is acceptable. Make sure plugs do not rotate when tightening retaining nut.
33. Install new screw clamp on lower radiator hose. Connect lower radiator hose to radiator and tighten clamp.
34. Install lower radiator support bracket. PROCEED TO STEP 36 and continue.
CHEMICAL FLUSH PROCEDURE
WARNING
WEAR RUBBER GLOVES DURING THIS STEP.m CHEMICAL CLEANER MAY CAUSE SKIN IRRITATION.
35. Partially raise vehicle.
36. Install radiator draincock.
37. Lower vehicle.
38. DO NOT add chemical cleaner to the coolant recovery bottle. Using a funnel, slowly add one (1) bottle of chemical cleaner (F8AZ-19A503-M) into the HEATER RETURN HOSE (Figure 8).
NOTE
THE RECOMMENDED CHEMICAL CLEANER MUST BE USED.
39. Connect and clamp the heater return hose to the water pump fitting.
40. Slowly fill cooling system with water. Squeeze upper radiator hose to purge air from system as water is added. Coolant level must be filled to the top of the clear portion of the coolant recovery bottle to completely clean the coolant bottle.
41. Start engine and raise RPM to 2000 RPM for 2 minutes. Do not exceed 2500 RPM.
42. Check cooling system for leaks.
43. Recheck coolant level. Add water, if necessary to bring level up to the top of the clear portion of the bottle.
44. Install coolant bottle pressure relief cap.
45. Run engine at idle until upper radiator hose is hot (when thermostat opens) approximately 12 minutes.
46. Turn engine off and let chemical solution soak for a minimum of thirty (30) minutes, while engine cools.
WARNING
COOLANT MAY BE HOT. REMOVE COOLANT PRESSURE RELIEF CAP.
47. Partially raise vehicle.
WARNING
WARNING WEAR RUB8IER GLOVES FOR THIS STEP. CHEMICAL CLEANER MAY CAUSE SKIN IRRITATION.
48. Remove radiator draincock.
49. Completely drain chemical solution and discard.
50. Lower vehicle.
51. Disconnect heater return hose from water pump fitting (Figure 9).
52. Install a 3/4" I.D. rubber cap on the water pump heater hose fitting (Figure 9).
53. Disconnect and plug radiator overflow hose from coolant recovery bottle. Discard clamp (Figure 10).
54. Attach a 4 foot section of 3/8" vinyl hose to overflow fitting on the coolant recovery bottle. Let vinyl hose hang over fender (Figure 10).
55. Install coolant pressure relief cap.
56. Connect garden hose (water supply) to heater return hose using 3/4" adaptor.
57. Turn garden hose on full pressure.
58. With engine off, flush engine for at least five minutes and until water is clear. Water will drain out of radiator draincock and the 4 foot vinyl hose.
59. Turn garden hose off and remove pressure relief cap from bottle.
60. Disconnect garden hose from heater hose. Let cooling system completely drain before proceeding.
61. Raise vehicle.
62. Install and tighten draincock.
63. Install splash shield.
64. Lower vehicle.
65. Remove rubber cap from the water pump.
66. Install new screw clamp on heater return hose and reconnect to water pump. Tighten clamp.
67. Reattach and secure alternator brace.
68. Remove 3/8" vinyl hose.
69. Unplug radiator overflow hose and install new screw clamp. Reconnect radiator overflow hose to coolant recovery bottle and tighten clamp.
70. Add one (1) bottle (16 oz) of heavy duty cooling system additive (FW-16) to coolant recovery bottle.
71. Add six (6) quarts of new coolant to coolant recovery bottle. Fill remainder of cooling system with water to top of clear lower portion of coolant recovery bottle.
72. Start engine and top off with water to top of clear lower portion of coolant recovery b6ttle (Figure 11).
NOTE
THE NEXT STEP MUST BE DONE BEFORE THERMOSTAT OPENS.
73. Raise engine RPM to 3000 RPM for 30 seconds and check for foaming inside the coolant recovery bottle. If foaming is present the coolant by-pass restrictor has not been installed. Turn oft engine and install the coolant by-pass restrictor (F7PE-8N030-M) contained in 1996-1997 bypass kit (F7DZ-8522-AB). Refer to coolant by-pass restrictor installation procedure in the bypass kit instructions.
74. Install coolant pressure relief cap.
75. Select maximum heater temperature and blower motor speed settings. Position control to discharge air from the instrument panel vents.
76. When vehicle reaches normal operating temperature, verify hot air from panel vents and a hot upper radiator hose.
77. CAUTION: If air discharge remains cool and engine coolant temperature gauge does not move, engine coolant level is low and must be filled. Stop engine, allow to cool and fill cooling system to top of clear lower portion of coolant recovery bottle.
78. Start engine and allow it to idle until normal operating temperature is reached. Hot air should discharge from panel vents. The engine coolant temperature gauge should maintain stabilized reading within the NORMAL range and upper radiator hose should feel hot to touch.
79. Shut engine off and allow engine to COMPLETELY COOL.
80. Check engine for coolant leaks.
81. IF NECESSARY. ADD COOLANT UNTIL LEVEL IS AT THE TOP OF THE CLEAR PORTION OF THE COOLANT BOTTLE (FIGURE 11).
82. INFORM CUSTOMER THE IMPORTANCE OF MAINTAINING COOLANT LEVEL IT'S RECOMMENDED THAT COOLANT CAN BE SAFELY FILLED TO THE TOP OF THE CLEAR PORTION OF THE COOLANT BOTTLE WHEN THE ENGINE IS COLD. THIS PROVIDES EXTRA RESERVE COOLANT.