Northern Lights — Bleeding the fuel system (SP10)
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
- Escaping diesel fuel under pressure can penetrate skin causing serious personal injury.
- Use a piece of cardboard or wood, rather than hands, to search for suspected leaks.
Procedure
- The fuel system is self-bleeding but may need manual bleeding after filter change, run-out of fuel, or component removal.
- Loosen bleed bolt 'A' on top of filter.
- Pump hand primer 'B' on fuel lift pump until pure fuel (no bubbles) escapes from bleed bolt 'A'. Tighten bleed screw 'A'.
- Loosen bleed screw or bolt 'C'. Pump hand primer 'B' until pure fuel escapes. Tighten bleed screw 'C'.
- If engine does not start, loosen a fuel line at the injector, crank until pure fuel escapes, and tighten. Do each line one at a time.
- After engine has started, use a piece of cardboard to look for fuel leaks.
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.