2009 Arctic Cat 150 ATV Service Manual, Page 11Get this manual
6Holding the tappet adjuster at the proper clearance, tighten the jam nut securely; then recheck tappet clearance7Place the cylinder head cover with new O-ring into position; then tighten the cover securely NOTE: The engine must be warm and the battery must be fully charged for this test
5While holding the throttle lever in the full-open position, crank the engine over with the electric starter until the gauge shows peak reading (five to 10 compression strokes)NOTE: The compression should be within range of 210-230 psi in the full-open throttle position
6If compression is abnormally low, verify the following itemsAStarter cranks engine overBGauge functions properlyCThrottle lever in the full-open positionKM703
8Install the timing inspection plug; then install the oil through and spring into the crankshaft
DValvetappet clearance correctEValve not bent or discoloredFValve seat not discoloredNOTE: To service valves, see Section 3
7Pour approximately 30 ml (1 fl oz) of oil into the spark plug hole, attach the gauge, and test compression8If compression is now evident, service the piston rings (see Section 3)