Northern Lights NL673 — Valve Clearances (SP6)
Adjustments · Cylinder head valve train
For the Northern Lights NL673, from the Northern Lights owner's manual.
Applies to: Northern Lights NL673
Before you start
- Valve adjustments should be done after the cylinder head bolts have been re-tightened.
Procedure
- Adjust valve clearance every 1000 hours, or as needed; engine 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 and adjust the clearance on both valves for this cylinder.
- Loosen the lock nut and adjust clearance with the adjustment screw.
- Clearance on both intake and exhaust valves is 0.008 in. (0.2 mm).
- Repeat for each cylinder; each set of valves must be adjusted individually.
- Replace the rocker arm cover; tighten cover nuts to 5 - 8 ft/lbs (0.8 - 2.3 kg/m).
Specs & values
- Valve clearance 0.008 in. (0.2 mm)
- Rocker arm cover nuts 5 - 8 ft/lbs (0.8 - 2.3 kg/m)
Full service-parts list: Northern Lights NL673 →
Source: Northern Lights owner'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.