Engines 2. To disengage the PTO: gases. While the engine is running, this heat is car- ried away by oil circulation, but if the engine is stopped suddenly, the turbocharger temperature may rise as much as 115°F (46°C). 2.1 Depress the foot brake pedal, trailer brake, clutch pedal, or To resume a previously selected engine speed, momen- tarily move the SET/RESUME switch to RESUME. 2.2 Flip the ON/OFF switch to OFF. The extreme heat may cause bearings to seize or oil seals to leak. 3. Do not idle the engine for excessively long periods. Adjust engine speed up or down by holding the SET/ RESUME switch at SET (accelerate) or at RESUME (decelerate) until the desired speed is reached.
Long periods of idling are not good for an engine because the combustion chamber temperatures drop so low the fuel may not burn completely. This will cause carbon to clog the injector spray holes and piston rings, and may result in stuck valves. NOTE: The resume engine speed memory is not maintained if the cruise control ON/OFF switch is turned OFF, or if the ignition is shut off. If the engine coolant temperature becomes too low, raw fuel will wash the lubricating oil off the cylinder walls and dilute the crankcase oil, causing all mov- ing parts of the engine to suffer from poor lubrica- tion. Engine Shutdown Cummins Engines 1.
With the vehicle stopped, apply the parking brakes, and place the transmission in neutral. CAUTION 2. It is important to idle an engine 3 to 4 minutes be- fore shutting it down. This allows the lubricating oil and the water to carry heat away from the combus- tion chambers, bearings, shafts, etc. This is espe- cially important with turbocharged engines. Stop the engine at the first sign of malfunction. Al- most all malfunctions give some warning to the op- erator before significant damage occurs. Many en- gines are saved because alert operators heed the warning signs (sudden drop in oil pressure, un- usual noises, etc.) and immediately shut down the engine.
Bearings and seals in the turbocharger are sub- jected to the high heat of combustion exhaust 4.8