FRIGID winter months are here, and colder weather on your skin means tougher conditions for diesel engines.
Whether it is simply trying to move a customer's truck into a service bay on a frosty morning or operating your own truck through the winter, International Truck and Engine Corporation offers the following guidelines for starting, warming up, and running diesel engines in cold weather to achieve better engine performance and extend engine lifecycle.
When the thermometer dips into the teens, begin using the proper cold-starting aids to get the best performance out of engines. These aids include glow plugs, block heaters, ether kits, and oil pan heaters. It's important to know which aids to use and follow the manufacturers' recommendations for the application and engine to ensure smooth starting and to avoid damage.
Glow plugs, which are standard on International T 444E, International VT 365, and Power Stroke diesel engines, are used to raise the temperature in the combustion chamber to aid cold engine starting. Because glow plugs enable engines to start instantaneously, no other starting aid is necessary down to -20°F and below.
In addition to standard glow plugs, International recommends using block heaters to raise the temperature of the coolant surrounding the cylinders and improve startability. A block heater can be activated as soon as the engine is shut down to prevent rapid cooling of the engine. All International engines can be equipped with block heaters for starting at temperatures below -20°F.
For temperatures below 10°F, International in-line, six-cylinder engines require an ether kit to start, as they do not come equipped with glow plugs (ether should never be used on the International T 444E or International VT 365). Ether kits inject a specific amount of ether into the intake manifold to ensure starting.
Be aware that ether is an extremely flammable material. It must not be used with the cold start and warm-up aid kit, which is recommended and approved for use only on mechanical engines (a fuel-fired flame preheats intake air). The cold start and warm-up kit is an alternative to ether on mechanical engines as a starting aid. It improves cold starting and minimizes white smoke.
When the temperature plummets below -20°F, an oil pan heater will aid cold starting and alleviate stall problems that can occur in frigid temperatures. Oil pan heating elements warm the temperature of the engine oil in the sump, improving its flow to ensure an uninterrupted supply of oil to the injector and other components. International in-line, six cylinder engines have oil pans designed with a heater plug port to better facilitate installation of the optional oil pan heater.
Once started, diesel engines need to be warmed-up in order to raise the coolant to an operational temperature of 160°F, preventing potential engine damage and enhancing performance. Warm-up aids include Cold Ambient Protection (CAP) — the hand throttle and an engine warm-up device. Standard on all International engines, CAP slowly increases engine idle speed to a preset maximum rpm to speed warm-up time. The CAP feature is automatically enabled when the intake air temperature is below freezing and coolant temperature is below 149°F for the International I-6 or 158°F for the V-8.
The hand throttle is standard on all electronic engines and sold separately for mechanical engines. It is used to manually raise engine idle speed to maintain coolant temperature and is operated by the driver of the vehicle. Newer electronic engines equipped with CAP minimize the need for hand throttle. However, hand throttle use is required on mechanical engines from 10°F and below.
Some diesels, including the International T 444E and International VT 365 engines, have an available engine warm-up device. Used as an exhaust system restrictor to increase load on the engine, the engine warm-up device speeds cab warm-up and reduces white smoke.
“Many truck owners overlook the importance of not only properly warming-up their diesel engines but guarding against extended idling and rapid cool downs to maximize their engine performance in cold weather,” says John Kemmet, manager, field service, International Truck and Engine Corporation. “In the winter months, it's vital for engine components to reach and maintain proper temperatures for operation to reduce risk of damage to engines, and in the end, keep trucks on the road.”
Once the engine is warmed-up to a temperature of 160°F, the engine must maintain this temperature, enabling the engine to run smoothly and adequately heat its truck cab. At this temperature, the coolant will keep the areas surrounding the cylinders warm enough to ensure complete combustion of the engine's fuel and air mixture. Complete combustion aids in reducing the accumulation of excessive carbon deposits on valve stems and guides.
An on/off fan and underhood air valve can also be used to maintain coolant temperature. On/off fans reduce air movement to help maintain adequate engine operating temperatures, and are recommended in temperatures dropping below -20°F to reduce air movement. Viscous fans often rotate at too high a rate of speed even in cold temperatures and thereby remove necessary heat from the engine by cooling the intake air. An on/off fan prevents this by rotating at higher RPMs only when cold air is needed.
Underhood air valves warm the air entering the engine by blocking the air inlet, taking warm air instead from under the hood. This needs to be used in vehicles where extended periods of idling cannot be avoided or for vehicles required to idle between stops. An underhood valve also prevents snow from blocking the air intake.
Cold weather checklist
In the transportation industry, it is vital to keep moving even under harsh weather conditions. To minimize problems, frequent maintenance is required in extremely cold temperatures. Following this checklist will help avoid unnecessary damage to the engine:
Check all rubber parts (hoses, fan belts) on a weekly basis.
Check all electrical wiring and connections for any frays or damaged insulation. Keep batteries fully charged and warm.
Keep tanks as full as possible to prevent condensation on exposed tank walls. Fill fuel tank when engine will be shut off for eight hours or more.
Check air cleaners and air inlet daily, or as necessary, when working in snow. An underhood air valve can also be used to ensure that snow and ice will not block air inlet.
Diesel engines require different grades of fuel during extremely cold weather. In temperatures below 20°F, use diesel fuel No. 1 or DF1, or diesel fuel No. 2 or DF2. Either fuel should have a minimum cetane rating of 45. When confronted with severe arctic cold weather conditions where the pour point of fuel requires low cetane, additives are required to supplement the fuel. Fuel suppliers or International dealers should be consulted.