Bulletin No. 1.00-3 Group No. 1.00 July 15, 1998 Page 1 of 1

ENGINE IDLING

EXTENDED IDLING OF YOUR ENGINE CAN LEAD TO TROUBLE

Idling of diesel engines for extended periods of time can cause real problems. Running engines at low idle causes the cooling system temperature to drop below normal. As a result, fuel in the combustion chamber is partially unburned and ends up in the lubricating oil. This is “oil dilution”, which affects the lubricity of the oil. The unburned fuel also contributes to the formation of sludge in the crankcase and deposits in the combustion chamber including pistons, rings and valves. The exhaust system also suffers as unburned fuel accumulates and begins to cause “slobber” or “wet stacking”. Engines should not run at low idle more than 3 to 4 minutes. If extended idling is necessary, increase engine speed to approximately half the speed range.