mr. fix it
Old Man with a Hat
Saw this today on Rock auto Newsletter.
Thought it's a pretty good how to use article.
The coolant temperature gauge needle on my '86 Mustang GT frequently hovers over the "A" in "NORMAL" printed on the gauge's face. My infrared thermometer showed the engine's metal thermostat housing was 210 F (99 C), confirming the coolant was indeed in the "normal" temperature range.
The original equipment steering knuckles on my '92 Dodge B250 van look like they were hammered into shape by a blacksmith. The brake calipers mounted on these imprecise knuckles are prone to binding up if caliper pins are not lubricated enough. My infrared thermometer lets me compare brake rotor temperatures to determine which calipers/brake pads are stuck.
Infrared thermometers (find under “Thermometer” in the "Garage Equipment" category of the "Tools & Universal Parts" tab) can dramatically speed up diagnostic work by reducing the need for disassembly and making it easy to compare identical parts. If there is one relay, fuel injector or microchip that is hotter or colder than all the rest, then that could be where to investigate first.
Something to be aware of when using an infrared thermometer is that its laser beam is just a laser pointer. It helps aim the thermometer but has nothing to do with actually measuring temperatures. The laser beam on an infrared thermometer is similar to having a laser sight mounted on a shotgun.
The thermometer measures the temperature of a circular area or "spot." Infrared thermometers are typically labeled with a Distance to Spot Ratio that tells you roughly how small the spot can be with the thermometer an ideal distance away from the object. For example a 12:1 ratio means the temperature spot will be about 1 inch (3 cm) in diameter on an object that is about 12 inches (30 cm) from the thermometer.
This means an infrared thermometer probably will not be able to accurately measure the temperature of a very small, isolated area like a spark plug's terminal or a bolt head. I sat a dime on top of a hot radiator hose (see photo) and surrounded the dime with strips of damp rag. The thermometer measured ~89 F. Without the rag pieces, the thermometer measured ~145 F. The laser beam was centered on the dime, but the thermometer was measuring the temperature of a larger circle/spot surrounding the dime. The temperature dropped if the cool rags were in the spot.
Different materials have unique thermal "emissivity." This means the temperatures of parts made from similar materials should be compared. For example, to study the performance of a radiator, compare the temperatures of the upper and lower radiator hoses instead of comparing the temperature of the rubber upper hose with the temperature of the aluminum radiator outlet tank.
RockAuto's infrared thermometers are designed to measure a wide range of temperatures on a variety of materials. Specialized infrared thermometers, like those used on humans, may be designed to calculate temperatures for only one type of material, such as human skin.
Tom Taylor,
RockAuto.com
Thought it's a pretty good how to use article.
The coolant temperature gauge needle on my '86 Mustang GT frequently hovers over the "A" in "NORMAL" printed on the gauge's face. My infrared thermometer showed the engine's metal thermostat housing was 210 F (99 C), confirming the coolant was indeed in the "normal" temperature range.
The original equipment steering knuckles on my '92 Dodge B250 van look like they were hammered into shape by a blacksmith. The brake calipers mounted on these imprecise knuckles are prone to binding up if caliper pins are not lubricated enough. My infrared thermometer lets me compare brake rotor temperatures to determine which calipers/brake pads are stuck.
Infrared thermometers (find under “Thermometer” in the "Garage Equipment" category of the "Tools & Universal Parts" tab) can dramatically speed up diagnostic work by reducing the need for disassembly and making it easy to compare identical parts. If there is one relay, fuel injector or microchip that is hotter or colder than all the rest, then that could be where to investigate first.
Something to be aware of when using an infrared thermometer is that its laser beam is just a laser pointer. It helps aim the thermometer but has nothing to do with actually measuring temperatures. The laser beam on an infrared thermometer is similar to having a laser sight mounted on a shotgun.
The thermometer measures the temperature of a circular area or "spot." Infrared thermometers are typically labeled with a Distance to Spot Ratio that tells you roughly how small the spot can be with the thermometer an ideal distance away from the object. For example a 12:1 ratio means the temperature spot will be about 1 inch (3 cm) in diameter on an object that is about 12 inches (30 cm) from the thermometer.
This means an infrared thermometer probably will not be able to accurately measure the temperature of a very small, isolated area like a spark plug's terminal or a bolt head. I sat a dime on top of a hot radiator hose (see photo) and surrounded the dime with strips of damp rag. The thermometer measured ~89 F. Without the rag pieces, the thermometer measured ~145 F. The laser beam was centered on the dime, but the thermometer was measuring the temperature of a larger circle/spot surrounding the dime. The temperature dropped if the cool rags were in the spot.
Different materials have unique thermal "emissivity." This means the temperatures of parts made from similar materials should be compared. For example, to study the performance of a radiator, compare the temperatures of the upper and lower radiator hoses instead of comparing the temperature of the rubber upper hose with the temperature of the aluminum radiator outlet tank.
RockAuto's infrared thermometers are designed to measure a wide range of temperatures on a variety of materials. Specialized infrared thermometers, like those used on humans, may be designed to calculate temperatures for only one type of material, such as human skin.
Tom Taylor,
RockAuto.com
