Cold Cranking Amps (CCA) is a measurement of a battery’s ability to start a car engine at 0*F. If your car experiences 0*F, then CCA is as important as getting to work on time.
How do you measure Cold Cranking Amps, or CCA?
Technicians should evaluate CCA with every winter inspection, or at least once per year. You should get a report from the technician’s battery diagnostic tool indicating your battery’s potential stored energy.
CCA Report sent to customer to verify battery health
CCA is an inventory measurement that indicates the strength of the battery to “crank” over the engine.
In the old days cars and tractors actually had physical handles or “cranks” that rotated the crankshaft in order to engage the pistons and valves in the combustion process.
“Cranking Amps” then refers to how much power the battery has reserved to deliver to the starter motor.
The starter motor rotates the crank shaft, rather than a strong back reefing on a handle at the front of the engine.
“COLD” Cranking Amps is a spin on the cranking concept that matters to every motorist in a cold climate.
Not that cold has a terrible effect on Amps (it does in a way), but cold DOES have a striking effect on engine rotation.
Ever taken peanut butter on a chilly fall camping trip? Tried to stir it?
Rotating the moving parts of an engine at 0*F is a lot like stirring cold peanut butter. Most lubricants become stiff with a reduction in temperature.
In Alaska, drivers try to mitigate this problem by installing heaters to warm the engine before start up.
This reduces the amount of CCA necessary to start a car, but it does not fully compensate the increase in resistance.
How many CCA do I need to start my car at 0*F?
It depends on your engine size.
A good rule of thumb: 1CCA per cubic inch of gasoline engine displacement, 2CCA per diesel engine displacement.
Engine displacement is expressed in cubic centimeters (cc) or liters (L). To convert from Cubic Inches to Liters, multiply each liter by 61 (there are 61 cubic inches in one Liter).
If you drive a 2017 Subaru Outback with a 2.5L engine, you will take 1CCA X 61X2.5L= 152.5 CCA Battery will start your car with 30 seconds of cranking.
What if the engine does not “catch” or begin the combustion process after 30 seconds?
Then your battery is dead and you have to call for help.
This is why manufacturers DOUBLE the CCA requirement for batteries. Also, of you live in a place with well-below zero temperatures, this increases exponentially the need for more CCA.
In Interior Alaska, a good rule of thumb is FOUR-TIMES the required CCA indicates a healthy battery.
This means that a Subaru Outback battery should regularly store 450-600 CCA.
Make sure your car gets a CCA report with its annual inspection.
If your Subaru battery comes up at 200CCA, you know you have saved yourself a cold wait or a tardy at work, because you got the chance to swap it out before it stranded you!
