Diagnostic Information TM2361 (24JUN08) 9010-15-23 450DLC Excavator Operation and Tests 062608 PN=293 5 Reed Valve Check Check the reed valve for deformation or breakage. TX1002965 –UN–24JAN06 1—Reed Valve 2—EGR Valve 3—Exhaust Side 4—Intake Side If the reed valve is broken, bypass of intake air deteriorates air-fuel ratio, resulting in output lowering. Is reed valve (1) OK? YES: Go to Fuel System Test. NO: Repair or replace parts as necessary and retest. – – –1/1 9010 15 23 6 Fuel System Test Check fuel system in the following procedure. 1. Check the high pressure line and low pressure line for leaks, kinks, or obstructions. Check in the following order.
• Fuel filters (water separator and final filters). • Fuel tank (pump strainer). • Fuel system lines. 2. Check fuel lines, fuel filter, and inside of the fuel tank for freezing or waxing (cold temperatures). 3. Check the supply line inside the fuel tank for debris. 4. Supply fuel from a container other than the fuel tank. a. Start the engine, operate the machine, and check for trouble symptoms. b. Replace the fuel in the fuel tank and lines. c. Bleed air from fuel, and check for trouble symptoms again. Are any fuel system problems present? YES: Repair and replace necessary parts and retest. NO: Go to Exhaust System Check. – – –1/1