I.Conversion of Low Altitude System to High Altitude
PARTS INFORMATIONDescription Part Number
^ - EGR Vacuum Control 22515542 or equivalent Valve Assembly (High Altitude Application)
^ - Altitude Adjustment Kit 22516487 or equivalent
Kit Contents Quantity
Locknut 1
Seal 1
Metering Valve Screw 1
Label (P/N 14057201) 1
Dealers in high altitude areas should encourage owners who have moved to high altitude counties to purchase the service adjustment procedure outlined below, which is considered an owner maintenance expense. See attachment for a list of counties which the Environmental Protection Agency has designated as high altitude counties.
FIGURE 1 - EGR Vacuum Control Valve Assembly:
1. Replace the EGR vacuum control valve assembly (Figure 1) with the assembly shown in the parts information.
2. Perform the adjustments in this step as required depending on model year of vehicle.
A. On 1982 vehicles, install magnetic tachometer probe J-26925; run engine until it is at operating temperature. Set idle speed to specifications; turn engine off.
B. On 1983 vehicles, install timing meter J-33075 or equivalent, set pump timing -4~, and set idle speed to specifications. Diesel timing should be checked or adjusted at the same approximate altitude at which the vehicle will be driven.
3. Remove air cleaner and air crossover assemblies and install screen covers, J-26996-2.
FIGURE 2 - Injection Pump Assembly:
4. Install shop towel in the intake manifold valley area under the injection pump head to absorb any fuel leakage. Remove housing pressure tap plug and seal located on the rear of the pump (Figure 2).
5. Assemble locknut and new seal (O-ring) to metering valve stop screw as shown.
6. Install assembly in injection pump until locknut contacts pump housing. Tighten locknut.
7. Place transmission in Park, turn A/C off and start engine.
8. Loosen locknut and slowly turn metering valve stop screw clockwise until idle speed drops approximately 10 RPM.
9. Turn metering valve stop screw counterclockwise 2-1/2 turns and tighten locknut.
10. Check installation for fuel leaks and remove shop towel from intake valley.
11. Turn engine off.
12. Remove timing meter or magnetic tachometer probe and screened covers from intake manifold and reinstall parts removed.
FIGURE 3 - High Altitude Adjustment Label:
13. Type or print with ball point pen the dealer code and date in the space provided on the supplemental emission control label, P/N 14057201 or equivalent, Figure 3 (part of kit). The label must be placed next to the existing underhood emission control information label to the extent possible. The label should not be affixed to any equipment that can be easily detached from the vehicle. Wash off the area with soap and water, dry thoroughly, and apply the new label.
Suggested Time
The suggested time to perform High Altitude Adjustment and part replacement procedure listed above is 0.4 hour labor.