The optional engine coolant heater (RPO KO5) is designed to warm the coolant in the engine block area for improved starting in very cold weather (-29°C/-20°F). The use of the coolant heater helps reduce fuel consumption when a cold engine is warming up. The engine coolant heater coil is rated at 600 watts. The engine coolant heater coil operates from 110 volt AC external power supply. The coolant heater is required in Canada on a engine.

The coolant heater consists of a small electrical heating element inserted through the left rear water jacket hole in the engine block. This heating block is precisely machined. The heating block uses a rubber O-ring to seal the coolant passage. A weather shield on the cord is provided to protect the plug when not in use.

Check all electrical connections if the coolant heater fails to heat the coolant. Check the following if the coolant heater fails to heat the coolant:

1. Check for 110 volt AC external power source.
2. Check for continuity to ground of heater cord.
3. Check for shorts to ground of heater cord.
4. Replace cord as required.
5. Check heater if the external power source and the cord are OK.
6. The heater should show continuity.
7. Replace as required.