Usage:
All Caterpillar Truck Engines
With the winter season upon us it is appropriate to remind customers of the need to prepare in order to avoid:
- * hard starting
- * excess white smoke
- * not reaching full engine operating temperature
- * complaints of cold cab and bus bodies
- * valve sticking
- * accelerated wear
- * excess white smoke
Measures that will minimize or eliminate these problems and complaints are included in the Operation And Maintenance Manual "Cold Weather Recommendations for On-Highway Truck Engines", Form SEBU6740. These recommendations have also been included in the regular Operation and Maintenance Manuals for some on-highway engines. Specific recommendations for 3116 Engines in Chevrolet Kodiak and GMC Topkick trucks were also included in the General Motors "What's New" publication dated December 1993 and Truck Engine News dated January 1994. Some of these recommendations are included in this article as "Cold Weather Recommendation Charts".
An additional help, on Chevrolet and GMC Trucks equipped with air conditioning, is to used the "MAX" mode on the heater/air conditioner control. The "MAX" mode will recirculate cab air rather than drawing cold outside air across the heater core. Recirculation uses available coolant heat to raise the temperature of the air already inside the cab. When not in the "MAX" mode the available coolant attempts to warn a constant stream of colder outside air.
NOTE: The "MAX" mode should only be used when the truck is parked. This due to the possibility of windshield fogging.
The engine should be idled at 1000 rpm or more to provide the creates amount of heat.
The inability of the engine to warm up quickly and/or maintain its temperature at idle or low load is often thought to be a defect in the engine. This seldom the case. The only components of the engine that governs temperature is the thermostat. A thermostat that fails in the open position or leaks excessive coolant to the radiator will cause a slow warm-up and rapid cool-down. However, the thermostat is seldom a factor in most cases we hear about.
Usually, complaints of inadequate heat, slow warm-up and rapid cool-down relate to items in the installation that cause engine that cause engine heat to be rapidly dissipated. Many attachments suggested in the Cold Weather Recommendations address ways to conserve the heat the engine generates. Many attachments suggested in the Cold Weather Recommendations address ways to make engine maintain coolant at the proper temperature for long engine life and cab heating. These attachments are available through the truck or bus manufacturer or local suppliers.
Only engine components, such as a defective thermostat, are covered by the engine warranty. In most cases, investigation of cold operating complaints and vehicle modifications will not be paid for by Caterpillar. This policy is summarized in Warranty Update Number 9414, dated 10/24/94, and distributed to Caterpillar Dealers via E-Mail.
Engine over cooling complaints not caused by defective engine components, should be referred to the appropriate truck/bus servicing dealer and/or representatives of the manufacturer for resolution.
Cold Weather Recommendation Charts
Each matrix was constructed to assist dealers and customers equip and operate their Caterpillar diesel truck engines effectively in frigid weather. Starting aids should be selected that allow the engine to start at the various temperature ranges without the need for extended cranking periods.
If extended idling periods are unavoidable, some or all of the idle temperature and coolant warmup devices should be considered based on the maximum temperatures expected. The goal is to maintain a minimum engine coolant temperature of 160°F (71°C).
