Coolant in Combustion Chamber
Coolant in Combustion Chamber

Cause

Correction

DEFINITION: Excessive white smoke and/or coolant type odor coming from the exhaust pipe may indicate coolant in the combustion chamber. Low coolant levels, an inoperative cooling fan, or a faulty thermostat may lead to an overheating condition which may cause engine component damage.

Note: While not always conclusive, use of hydrocarbon block test kits may reveal hydrocarbons indicating combustion chamber gases in cooling system. It is important to follow the kit instructions. This is not a substitute for service information. Combustion leak tests are available from a wide variety of aftermarket suppliers.

  1. A slower than normal cranking speed may indicate coolant entering the combustion chamber. Refer toEngine Will Not Crank - Crankshaft Will Not Rotate.
  2. Remove the spark plugs and inspect for spark plugs saturated by coolant or coolant in the cylinder bore.
  3. Inspect by performing a cylinder leak-down test. During this test, excessive air bubbles within the coolant may indicate a faulty gasket or damaged component.
  4. Inspect by performing a cylinder compression test. Two cylinders side-by-side on the engine block, with low compression, may indicate a failed cylinder head gasket. Refer toEngine Compression Test.

Faulty cylinder head gasket

Replace the head gasket and components as required. Refer toCylinder Head Cleaning and Inspection andCylinder Head Replacement.

Warped cylinder head

Replace the cylinder head and gasket. Refer toCylinder Head Replacement.

Cracked cylinder head

Replace the cylinder head and gasket. Refer toCylinder Head Replacement.

Cracked cylinder liner

Replace the components as required.

Cylinder head or block porosity

Replace the components as required.