105419-2610 ZEXEL 9 420 611 711 BOSCH GOVERNOR 9420611711 1054192610

Proper operation and maintenance are key factors in obtaining the maximum life and economy of the engine. Following the directions in this manual will lower operating costs.After the engine is started and the cold idle operation is completed, the truck can be operated at low speed and low power. The engine will reach normal operating temperature faster when driven at low speed and low power demand than when idled at no load. Typically the engine should be up to operating temperature by just driving through the yard toward the open road.Engine Operation
* Begin operating the engine at low load. After normal oil pressure is reached and the temperature gauge begins to move, the engine may be operated at full load.* To get the vehicle in motion, use a gear that will result in a smooth, easy start without increasing engine speed above low idle or slipping the clutch. Engage the clutch smoothly. Abrupt or jerky starts put stress on the drive train and waste fuel.* Use progressive shifting to reduce fuel consumption. Progressive shifting is using only the rpm required to make an upshift into the next gear. The amount of rpm required to make an upshift increases as the truck speed increases unless upshifts are made on upgrades. Experience with your truck will show you how much rpm is required to make upshifts under various conditions.* If the truck can be operated in a higher gear after the desired speed is reached, select the highest gear available that will pull the load. By following this recommendation, you will lower your fuel costs, since your engine will be operating at the lowest rpm required to pull the load.Uphill Operation
On upgrades, begin downshifting when the engine rpm starts to approach peak torque (1100-1200 rpm) speed. Fuel economy will be best if you let the engine lug back to around this speed before you downshift. Downshift until a gear is reached in which the engine will pull the load. Allowing the engine to lug below peak torque is permissible if the truck is cresting the top of a hill without downshifting.However, note that extended operation in a lug condition will raise exhaust temperature and cylinder pressure and can lead to reduced engine life.Downhill Operation
Do NOT allow the engine rpm to exceed 2300 rpm, engine damage can result. If equipped with an exhaust brake, do not exceed 2100 rpm.
* When operating the vehicle downhill, do not coast or put the transmission in NEUTRAL.* Select the correct gear that does not allow the engine speed (rpm) to exceed the limits above and use the engine retarder and/or brakes to limit the speed of the truck.* A simple rule to follow is to select the same gear that would be required to go up the grade. However, DO NOT allow the engine to overspeed.For more information on economical operation of this engine, refer to form LEDT5092, Driving Techniques for Maximum Fuel Economy.