Northern Lights — SP6 Valve Clearances
Adjustments · cylinder head
From a Northern Lights operator's manual covering: M20C, M844LW2, M844W2. Check it applies to your exact model before use.
Applies to: Northern Lights M20C, Northern Lights M844LW2, Northern Lights M844W2, Northern Lights 844W2 / 844LW2 engine, Northern Lights 844W2 engine, Northern Lights 844LW2 engine
Before you start
- Valve adjustments should be done after the cylinder head bolts have been re-tightened.
Procedure
- Adjust valve clearance after 1000 hours or as needed; engine must be cold and NOT running.
- Turn the engine over by hand until the inlet valve starts to open and exhaust starts to close (valves rocking).
- Turn the crankshaft one more full turn; align the top mark of the crank pulley with the top mark of the timing gear case.
- Loosen the lock nut and adjust clearance between rocker arm and valve guide with the adjustment screw.
- Clearance on both intake and exhaust valves should be 0.008 in. (0.2 mm).
- Repeat for each cylinder; each set of valves must be adjusted individually.
- Replace the rocker arm cover and tighten cover nuts to 5 - 8 ft/lbs (0.8 - 2.3 kg/m).
Tools required
Tool links are Amazon searches (affiliate links); manufacturer special tools may only be available from a dealer.
Specs & values
- Valve clearance 0.008 in. (0.2 mm)
- Rocker cover nuts 5 - 8 ft/lbs (0.8 - 2.3 kg/m)
Full service-parts list: Northern Lights M20C →, Northern Lights M844LW2 →, Northern Lights M844W2 →
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.