Coolant in Engine Oil

2008 Suzuki Swift +SECTION Coolant in Engine Oil
Cause Correction
Definition :  Foamy or discolored oil or an engine oil "overfill" condition may indicate coolant entering the engine crankcase. Low coolant levels, an inoperative cooling fan, or a faulty thermostat may lead to an "over temperature" condition which may cause engine component damage. Contaminated engine oil and oil filter should be changed.
  1. Inspect the oil for excessive foaming or an overfill condition. Oil diluted by coolant may not properly lubricate the crankshaft bearings and may lead to component damage. Refer to Main Bearing Noise  and Connecting Rod Bearing Noise Symptom .
  2. Inspect the cylinder head casting plugs for coolant leakage. Refer to Cylinder Head Cleaning and Inspection (Off Vehicle)  or Cylinder Head Cleaning and Inspection (On Vehicle) .
  3. Inspect by performing a Cylinder Leak-Down Test. During this test, excessive air bubbles within the cooling system 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 to Engine Compression Test .
Faulty cylinder head gasket Replace the head gasket and components as required. Refer to Cylinder Head Replacement .
Warped cylinder head Replace the cylinder head gasket. Refer to Cylinder Head Replacement .
Cracked cylinder head Replace the cylinder head and gasket. Refer to Cylinder Head Replacement .
Cracked engine block Replace the components as required.
Cylinder head, block, or manifold porosity Replace the components as required.
Leaking engine oil cooler Replace components as required.
Leaking cylinder head casting plugs Reseal the cylinder head casting plugs. Refer to Cylinder Head Cleaning and Inspection (Off Vehicle)  or Cylinder Head Cleaning and Inspection (On Vehicle) 
RENDER: 1.0x

NO RELATED

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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • You smell fuel, burning insulation, or see smoke.
  • Brakes feel soft, pull hard to one side, or make grinding noises.
  • The engine overheats, stalls repeatedly, or misfires under load.
  • You are missing required tools, torque specs, or safe lifting equipment.
  • You are not confident in the next step or safety outcome.