M11 Industrial Operation and Maintenance – Engine Noise Excessive — Combustion Knocks

Engine is operating at low ambient temperature

Check the winterfront, shutters, and under-the-hood air. Use under-the-hood intake air in cold weather. Refer to Procedure 101-004 (Cold Weather Starting) in Section 1.

Ether starting aid is malfunctioning

Repair or replace the ether starting aids. Refer to the OEM service manual.

Fuel grade is not correct for the application or the fuel quality is poor

Operate the engine from a tank of high-quality fuel. Refer to Procedure 018-002 (Fuel Recommendations and Specifications) in Section V.