SCREEN 1380636 - Caterpillar

Engine: Truck with Hydraulic Electronic Unit Injection (HEUI)
3116 Engine: Truck
All Engine: Machine with Mechanical Unit Injection
3116Truck Engine News SEBD6781, 1 August 2005, "Cold Weather Operation Reminder". Disregard this article. Refer to the following article.Note: The full open temperature for the 119-3075 Water Temperature Regulator is 94 °C (201 °F). The full open temperature for the 115-4223 Water Temperature Regulator is 97 °C (207 °F).Product Updates
There have been recent product updates in order to help maintain heat in the engine during cold weather.Low Leak Thermostat
The low leak thermostat includes a single jiggle valve in order to vent air from the system. Low leak thermostats have a resilient valve seat in order to reduce the coolant passage to the radiator. Former thermostats that use two valves and thermostats that were seated metal to metal bypass more coolant to the radiator. The 119-3075 Water Temperature Regulator which is full open at 94 °C (201 °F). This is effective on the 3116 9gk1-UP Truck Engine. The 119-3075 Water Temperature Regulator is effective for General Motors models prior to 1996. A 115-4223 Water Temperature Regulator is also available. The 115-4223 Water Temperature Regulator is full open at 97 °C (207 °F). The alarm switch for the warning indicator must be changed if you use the 115-4223 Water Temperature Regulator. To avoid false warnings, this must be done on vehicles that are equipped with a high coolant temperature warning indicator. The alarm switch is provided by the truck manufacturer. The 119-3075 Water Temperature Regulator and the 115-4223 Water Temperature Regulator can be used on all 3116 Truck Engines.Low Speed Viscous Fan Clutch
The low speed viscous fan clutch is available on some General Motors applications. Since 1995, KUW has been a regular option that is available in production for buses. The KUW option is required on all buses that are built for Canada. This is used for all 1995 model year and later. A service clutch is required for buses that are 1994 and older. Either fan clutch can be retrofitted to all Topkick and Kodiak buses that are used with 3116 Engines.Run the engine of a truck or a bus that is equipped with a low speed viscous fan clutch, at 1500 to 1800 rpm. This is done in order to disengage the clutch. When the low speed viscous fan clutch is disengaged, the fan will rotate at 250 rpm regardless of the engine speed.When the low speed viscous fan clutch is engaged, the fan will rotate faster than engine speed. Cold air is drawn across the radiator, and aftercooler cores. Also, the cold air is blown over the engine. For the best warm-up at idle, the engine speed should be 1200 to 1400 rpm. The most rapid warm-up is achieved when the engine is put under a light load, rather than at idle.On Chevrolet and General Motors Corporation Trucks that are equipped with an air conditioner, you can achieve reduced time on engine warm-up. Set the air conditioner to the MAX position