Low Altitude To High Altitude Modification & Adjustment

1. Stop engine and apply parking brake. Disconnect rubber hose from air switching valve, located on front left side of engine. Connect delay valve to disconnected hose and valve. Ensure rubber hose on "A" side of delay valve is connected to vacuum line. Ensure rubber hose on "B" side of delay valve is connected to air switching valve.
2. Remove air cleaner. Remove 3 rubber caps from altitude compensation air passages on carburetor. Install 3 rubber hoses attached to compensator into these air passages. Install air cleaner. Adjust engine speed and ignition timing.

Fig 1: High Altitude Emission Control System (Trooper II)

Courtesy of ISUZU MOTOR CO.