Engine - High Altitude Modifications
84mitsubishi03
SUBJECT:
1985 TRUCK HIGH ALTITUDE MODIFICATIONS
NO. STB-84-25-003
DATE August 1984
MODEL 1985 Trucks
VEHICLES TO BE MODIFIED
1985 turbo diesel and gasoline trucks distributed to 49-state high altitude markets must be modified for high altitude operation before sale. The procedure for 1985 turbo diesel trucks is the same as for 1984 turbo diesel trucks and is described in STB-83-25-002 dated September, 1983. The procedure for 1985 gasoline trucks is presented in this bulletin.
HIGH ALTITUDE AREAS
High altitude market areas are the same as 1984. They are listed in STB-83-25-007 dated December, 1983.
PARTS REQUIRED
Two high-altitude kits are available for 1985 gasoline trucks:
MD089717 for 2.0L engine vehicles
MD089718 for 2.6L engine vehicles
Each of the above kits contains a high-altitude compensator, vacuum hose assembly and an emission control update label.
MODIFICATION PROCEDURE
The modification procedure is in three steps:
1. Adjust ignition timing.
2. Install high-altitude compensator kit.
3. Apply vehicle emission control update label.
These steps are described in detail below and on the following page.
IGNITION TIMING
Adjust ignition timing to the following specifications, following Service Manual procedures:
2.0L engine 10~ +/- 2~ BTDC
2.6L engine 12~ +/- 2~ BTDC
NOTE: Be sure idle speed remains within specifications when timing is adjusted. Refer to emission control under hood label for idle speed specifications.
FIGURE 1:
FIGURE 2:
FIGURE 3:
HIGH ALTITUDE COMPENSATOR
Attach the HAC to the brake master cylinder reservoir as shown in Figure 1. Remove and discard the rubber caps and install the hose as shown in Figure 3. Be sure the tangs are oriented as shown.
FIGURE 4:
VEHICLE EMISSION CONTROL INFORMATION UPDATE LABEL
Install the label as shown in Figure 4.
Remember! The sale of vehicles not configured to meet high-altitude requirements would violate federal emission regulations.
WARRANTY CONSIDERATION
Normal warranty procedures apply.