Northern Lights NL673 — Cooling System Flushing
Maintenance · cooling_system
For the Northern Lights NL673, from the Northern Lights operator's manual.
Applies to: Northern Lights NL673
Before you start
- Cooling water reaches extremely high temperatures.
- Allow engine to cool before working on cooling system.
Procedure
- Flush every 2500 hours or every 12 months, whichever comes first.
- Remove radiator cap and open drain cocks on radiator and engine block.
- Pour clean water into radiator until water from radiator is clear.
- Close radiator drain and continue flushing until water from engine drain is clear.
- Open all drain cocks and drain completely.
- Close drain cock and refill with recommended coolant mixture.
- Use 50% water / 50% ethylene glycol antifreeze mix.
- Check hoses and connections and repair any leakage.
Specs & values
- 2500 hours or 12 months
- 50% water / 50% ethylene glycol
Full service-parts list: Northern Lights NL673 →
Source: Northern Lights operator's manual. Steps and values are as documented; always cross-check against the official manual and any later revisions for your exact serial number before servicing.