Northern Lights — Cooling system flushing (SP14)
Maintenance
From a Northern Lights operator's manual covering: M16, M20, M20C, M844, M844L, ML844, ML844L, NL844. Check it applies to your exact model before use.
Applies to: Northern Lights M20C, Northern Lights M844, Northern Lights M844L, Northern Lights ML844, Northern Lights ML844L, Northern Lights NL844, Northern Lights 844 / 844L engine, Northern Lights 844L engine
Before you start
- Use extreme caution when working on hot engines to avoid burns. Allow engine to cool before working on the cooling system.
Procedure
- Flush the cooling system every 600 hours or every 12 months, whichever comes first.
- Marine: Remove expansion tank cap and drain engine block. Open block drain cock. Remove hose from bottom of heat exchanger tank.
- Marine: Pour clean water into expansion tank until water from drains is free of discoloration and sediment. Drain completely, close drains and refill with recommended mixture.
- Industrial: Remove radiator cap and open drain cocks on radiator and engine block.
- Industrial: Pour clean water into radiator until clear of discoloration; close radiator drain and continue flushing until engine drain water is clear.
- Industrial: Open all drain cocks and drain completely; close drain cock and refill with recommended coolant mixture.
- Industrial: Clean leaves, dust and other debris off radiator fins.
- Check hoses and connections and repair any leakage.
Specs & values
- Use 50% water/50% ethylene glycol antifreeze mix
Full service-parts list: Northern Lights M20C →, Northern Lights M844 →, Northern Lights M844L →, Northern Lights ML844 →, Northern Lights ML844L →, Northern Lights NL844 →
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.