Spark Plug; Muffler/Spark Arrester; Transmission Lubricant - Arctic Cat DVX 90/90 UTILITY Service Manual

8. If compression is now evident, service the piston
rings (see Steering/Frame/Controls section - Servic-
ing Top-Side Components).

Spark Plug

A light brown insulator indicates the plug is correct. A
white or dark insulator indicates that the engine may need to
be serviced or the carburetor may need to be adjusted. To
maintain a hot, strong spark, keep the plug free of carbon.
CAUTION
Before removing the spark plug, be sure to clean the
area around the spark plug. Dirt could enter engine
when removing or installing the spark plug.
Adjust the gap to 0.6-0.7 mm (0.024-0.028 in.) for proper
ignition. Use a feeler gauge to check the gap.
When installing the spark plug, be sure to tighten it to
specifications. A new spark plug should be tightened 1/2
turn once the washer contacts the cylinder head. A used
spark plug should be tightened 1/8 - 1/4 turn once the
washer contacts the cylinder head.

Muffler/Spark Arrester

To clean the arrester, use the following procedure.
! WARNING
Before removing the muffler/spark arrester, wait for it to
cool to avoid burns.
1. Remove the cap screw (1) securing the spark arrester
assembly (2) to the rear of the muffler. Account for a
gasket.
2. Clean the screen (3) with a brush and parts-cleaning
solvent. Dry with compressed air. If the screen has
any holes or tears, it must be replaced.
ATV-0051
Before installing the spark arrester, wait for the muffler
to cool to avoid burns.
3. Install the spark arrester in the muffler and secure
with the cap screw. Tighten securely.
ATV-0052A

Transmission Lubricant

1. Park the ATV on level ground.
! WARNING
KM139A
KM140B
KM139
9