Coolant is Critical to your Subaru:
The Results of Overheating
When the engine overheats, a number of dangerous problems can arise that drastically affect engine operation:
- Knocking and pinging develop from the detonation of overheated fuel.
- Hot spots can develop in the combustion chamber and cause the air/fuel mixture to ignite before spark occurs, and possibly far before TDC. This “pre-ignition” results in loss of power as the cylinders fight each other and the smooth rotation of the crankshaft becomes erratic. On OBD II vehicles, this may result in an illuminated MIL and a misfire DTC.
- Valves and guides may be damaged from the high
- Camshafts can seize or break from the expansion of metal components.
- Pistons may be damaged from heat expansion or burn through. Piston swell can ruin the cylinder wall.
- Head gaskets may be damaged or burn though. Any coolant entering the crankcase can damage the crank bearings.
- The radiator can split under excessive expansion of the coolant vaporizing and turning to steam.
- Hoses can split or burst under increased pressure.
In severe cases of overheating, the entire engine can be badly damaged or destroyed.