Rick's Free Auto Repair Advice

Car losing coolant

Car losing coolant — What to check

Internal combustion engines don’t consume coolant unless there’s a major problem. So, if your car is losing coolant, it’s either leaking internally and burning it inside the combustion chamber or leaking it externally.

Start by checking for the signs of external leaks

Look for puddles under the vehicle in the morning.

coolant loss. Coolant leak on ground

Coolant puddles under your car are a sign of a leak.

Look for signs of dried coolant

antifreeze leak near radiator

Dried coolant

Check for a leaking coolant reservoir

leaking coolant reservoir

Leaking coolant around the sea

Perform a cooling system pressure test

If you can’t see any signs of a leak, rent a cooling system pressure tester and pressurize the system. It should hold pressure for at least 15-mins. If it doesn’t there IS a leak somewhere

cooling system pressure tester

Cooling system pressure tester

Still have coolant loss? Check for a head gasket leak

Here’s one of the easiest ways to check for a head gasket failure that results in coolant consumption. Perform this in the morning before the engine is started.

Remove all the spark plugs
Clip sheets of paper towels about 6″ above each spark plug hole.
Remove the fuel pump fuse and crank the engine.
If there’s coolant in the combustion chambers, it’ll spit the coolant out onto your paper towels.
That’s proof positive that you have a head gasket problem because coolant should never be in a combustion chamber

Perform a combustion gas test to check for a head gasket breach

Rent a combustion gas tester from any auto parts store and follow the directions. If there’s combustion gas in the coolant, there’s a head gasket breach.

combustion gas test
©, 2022 Rick Muscoplat

Posted on by Rick Muscoplat



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