EM-8 ENGINE MECHANICAL - Engine Tune-up (jl If there is an idle l imiter cap on the idle mixture Limiter Cap Type adjusting screw, remove it. EC0005 SST Type (k) Use SST if necessary. SST 09243-00020 EM1524 3. ADJUST IDLE SPEED AND IDLE MIXTURE (a) Start the engine. Idle Speed Adjusting Screw (b) Using a CO meter to measure the CO concentration in the exhaust. turn the idle speed and idle mixture adjusting screws to obtain the specified concentra tion value at idle speed. Idle speed: MIT 650 rpm AIT 750 rpm EM ' 525 4. INSPECT CO CONCENTRATION (a) Check that the CO meter is properly calibrated. Tachometer (b) Race the engine 30 - 60 seconds at about 2,000 rpm before measuring concentration.
(e) Wait 1 - 3 minutes after racing the engine to allow the concentration to stabilize. rpm ECO' 63 (d) Insert a testing probe at least 40 cm (1.3 ft) into the tailpipe, and measure the concentration within a short time . Idle CO concentration: 1.5 ± 1.0 % • If the CO concentration is within specification this adjustment is complete . • If the CO concentration is not within specifica tion. turn the idle mixture adjusting screw to obtain the specified concentration value. • If the CO concentration cannot be corrected by adjusting the idle mixture. see table below for EC1347 other possible causes .