In areas where winter driving can involve cold temperatures, ice and snow, special attention should be given to certain vehicle maintenance items.
When talking with customers about installing a new battery or new tires, or performing cooling system maintenance before the temperature drops below freezing, keep these winter car care tips in mind.
Batteries
When a battery is subjected to a high discharge rate, as is the case with cold-start cranking, the battery may be completely discharged in a short period of time due to the fact that cold temperatures slow down the chemical reaction in the battery. Only a very small percentage of the total active material and electrolyte within a battery cell can be utilized under colder conditions. The result is the battery's energy storage capacity is greatly reduced. Furthermore, a cold engine requires more energy to start, with up to three times the cranking load of a warm engine.
When selecting a replacement battery, refer to the manufacturer's battery recommendations. To guarantee satisfactory performance at low temperatures, it is essential to select a battery of sufficient size and power. (Fig. 6)
At subzero temperatures, the capacity of a typical battery at full charge is only 45% of its capacity at 80°F.
Sometimes a battery test will show satisfactory performance, yet the battery will fail during service. Some common reasons why good batteries can fail:
• Accessories left on
• Excessive parasitic drains
• Faulty charging system
• Excessive electrical load, often from add-on accessories
• Faulty battery connections
• Improper previous charging
• Frozen battery due to being discharged and left in freezing temperatures
Tires
Before winter sets in, check tire tread depth and pressure. Remind customers that pressure in tires drops as the outside temperature drops.
All gases change pressure as their temperature changes. As a rule of thumb, tire pressure will change about 1 psi (7 kPa) for every 10°F decrease in temperature -- dropping when it gets colder outside, rising when it gets warmer. Tire pressure should be set to the specified Tire Information Label pressure at the lowest seasonal temperature the vehicle will encounter during operation.
During colder conditions on a vehicle equipped with a tire pressure monitor system, the air pressure in a cold tire may be at the pressure where the system is required to warn the driver by illuminating the low tire pressure light or displaying a Check Tire Pressure message. However, that same tire will rise in temperature and pressure as the customer drives, which may cause the message and/or light to go out. (Fig. 7)
To avoid a Check Tire Pressure message or warning lamp due to extreme temperature changes, do the following:
• Use an accurate, high quality tire pressure gauge
• Adjust the tire pressure to the specified value when the tire temperature is at the lowest
expected temperature. Never set the tire pressure below the label value regardless of tire
temperature or outside temperature
• Re-learn the TPM sensors and adjust the tire pressure to the specified values after every
tire rotation
Cooling System
The cooling system uses a coolant to transport heat energy away from the engine. Coolant is a mixture of water and chemical additives. The additives provide corrosion protection and lubrication, raise the boiling point, lower the freezing point, and provide the chemical buffers and sacrificial ions to limit corrosion of the various metallic materials used in today's engines.
According to the U.S. Department of Transportation, coolant-related failures are a major cause of mechanical breakdown. Inspection results during a National Car Care month revealed:
• 21% of the vehicles had low, leaking or dirty coolant
• 11% of the vehicles had at least one worn or unsatisfactory belt
• 4% of the vehicles needed to have hoses replaced
Check the surge tank reservoir for a proper fluid level. In addition, use a cooling system pressure tester to check the pressure cap and cooling system. The cooling system should hold the rated pressure for two minutes.
The pressure cap seals and pressurizes the cooling system. As the pressure builds, the boiling point of the coolant goes up as well. The cap contains a blow-off or pressure valve and a vacuum or atmospheric valve. The pressure valve is held against the seat by a spring of predetermined strength, which protects the radiator by relieving pressure exceeding the rated pressure.
The vacuum valve is held against the seat by a spring, which permits opening of the valve in order to relieve vacuum created in the cooling system as it cools off. The vacuum, if not relieved, might cause the radiator to collapse. Replace the cap if it is not sealing or venting properly. (Fig. 8)
To maximizing the service life of cooling system components:
• Perform a visual inspection and a squeeze test with your finger and thumb of the coolant
hoses as part of a vehicle's regular maintenance. Remember, Electro Chemical
Degradation (ECD) occurs within two inches of the ends of a hose
• Check for electrolysis (cause of ECD) with a voltmeter. Any voltage reading over 0.3 V
indicates stray voltage is finding its way into the coolant
• Verify coolant concentration using a refractometer, as it can work with both ethylene glycol
and propylene glycol.
• Flush the cooling system every two years if designed with ethylene glycol (green coolant),
which reduces the possibility of scale or harmful sediment build-up that can decrease
cooling performance, freeze protection and hose life
• Various methods and equipment can be used to flush the cooling system. If special
equipment is used, such as a back flusher, follow the instructions, and always remove the
thermostat before flushing
• Do not use conventional (green) coolant in a system designed for long-life DEX-COOL©
because service intervals will be reduced to two years or 30,000 miles
- Thanks to Mike DeSander
When talking with customers about installing a new battery or new tires, or performing cooling system maintenance before the temperature drops below freezing, keep these winter car care tips in mind.
Batteries
When a battery is subjected to a high discharge rate, as is the case with cold-start cranking, the battery may be completely discharged in a short period of time due to the fact that cold temperatures slow down the chemical reaction in the battery. Only a very small percentage of the total active material and electrolyte within a battery cell can be utilized under colder conditions. The result is the battery's energy storage capacity is greatly reduced. Furthermore, a cold engine requires more energy to start, with up to three times the cranking load of a warm engine.
When selecting a replacement battery, refer to the manufacturer's battery recommendations. To guarantee satisfactory performance at low temperatures, it is essential to select a battery of sufficient size and power. (Fig. 6)
At subzero temperatures, the capacity of a typical battery at full charge is only 45% of its capacity at 80°F.
Sometimes a battery test will show satisfactory performance, yet the battery will fail during service. Some common reasons why good batteries can fail:
• Accessories left on
• Excessive parasitic drains
• Faulty charging system
• Excessive electrical load, often from add-on accessories
• Faulty battery connections
• Improper previous charging
• Frozen battery due to being discharged and left in freezing temperatures
Tires
Before winter sets in, check tire tread depth and pressure. Remind customers that pressure in tires drops as the outside temperature drops.
All gases change pressure as their temperature changes. As a rule of thumb, tire pressure will change about 1 psi (7 kPa) for every 10°F decrease in temperature -- dropping when it gets colder outside, rising when it gets warmer. Tire pressure should be set to the specified Tire Information Label pressure at the lowest seasonal temperature the vehicle will encounter during operation.
During colder conditions on a vehicle equipped with a tire pressure monitor system, the air pressure in a cold tire may be at the pressure where the system is required to warn the driver by illuminating the low tire pressure light or displaying a Check Tire Pressure message. However, that same tire will rise in temperature and pressure as the customer drives, which may cause the message and/or light to go out. (Fig. 7)
To avoid a Check Tire Pressure message or warning lamp due to extreme temperature changes, do the following:
• Use an accurate, high quality tire pressure gauge
• Adjust the tire pressure to the specified value when the tire temperature is at the lowest
expected temperature. Never set the tire pressure below the label value regardless of tire
temperature or outside temperature
• Re-learn the TPM sensors and adjust the tire pressure to the specified values after every
tire rotation
Cooling System
The cooling system uses a coolant to transport heat energy away from the engine. Coolant is a mixture of water and chemical additives. The additives provide corrosion protection and lubrication, raise the boiling point, lower the freezing point, and provide the chemical buffers and sacrificial ions to limit corrosion of the various metallic materials used in today's engines.
According to the U.S. Department of Transportation, coolant-related failures are a major cause of mechanical breakdown. Inspection results during a National Car Care month revealed:
• 21% of the vehicles had low, leaking or dirty coolant
• 11% of the vehicles had at least one worn or unsatisfactory belt
• 4% of the vehicles needed to have hoses replaced
Check the surge tank reservoir for a proper fluid level. In addition, use a cooling system pressure tester to check the pressure cap and cooling system. The cooling system should hold the rated pressure for two minutes.
The pressure cap seals and pressurizes the cooling system. As the pressure builds, the boiling point of the coolant goes up as well. The cap contains a blow-off or pressure valve and a vacuum or atmospheric valve. The pressure valve is held against the seat by a spring of predetermined strength, which protects the radiator by relieving pressure exceeding the rated pressure.
The vacuum valve is held against the seat by a spring, which permits opening of the valve in order to relieve vacuum created in the cooling system as it cools off. The vacuum, if not relieved, might cause the radiator to collapse. Replace the cap if it is not sealing or venting properly. (Fig. 8)
To maximizing the service life of cooling system components:
• Perform a visual inspection and a squeeze test with your finger and thumb of the coolant
hoses as part of a vehicle's regular maintenance. Remember, Electro Chemical
Degradation (ECD) occurs within two inches of the ends of a hose
• Check for electrolysis (cause of ECD) with a voltmeter. Any voltage reading over 0.3 V
indicates stray voltage is finding its way into the coolant
• Verify coolant concentration using a refractometer, as it can work with both ethylene glycol
and propylene glycol.
• Flush the cooling system every two years if designed with ethylene glycol (green coolant),
which reduces the possibility of scale or harmful sediment build-up that can decrease
cooling performance, freeze protection and hose life
• Various methods and equipment can be used to flush the cooling system. If special
equipment is used, such as a back flusher, follow the instructions, and always remove the
thermostat before flushing
• Do not use conventional (green) coolant in a system designed for long-life DEX-COOL©
because service intervals will be reduced to two years or 30,000 miles
- Thanks to Mike DeSander
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