Polaris Scrambler 9921620 - Manual (Page 92)

90
MAINTENANCE
Spark Plugs
Spark Plug Inspection
Normal Plug
The normal insulator tip is gray, tan or light brown. There will be few
combustion deposits. The electrodes are not burned or eroded. This
indicates the proper type and heat range for the engine and the service.
NOTE: The tip should not be white. A white insulator tip indicates
overheating, caused by use of an improper spark plug or
incorrect carburetion adjustments.
Wet Fouled Plug
The wet fouled insulator tip is black. A damp oil film covers the firing
end. There may be a carbon layer over the entire nose. Generally, the
electrodes are not worn. General causes of fouling are excessive oil,
use of non-recommended injection oil, improper use of the choke, or
incorrect carburetion adjustments.
Recoil Housing
To prevent possible engine damage,
always drain the recoil housing (1)
after operating the vehicle in very
wet conditions. This should also be
done before storing the vehicle.
Water will enter the recoil housing
if the starter handle is disengaged
from the rope guide when under
water.
The drain screw is located at the
bottom of the recoil housing. Use a
wrench to remove the screw. Be sure to reinstall the screw after
draining the housing.
NOTE: Do not open the crankcase drain unless the engine has
ingested water. On 4-cycle engines, some engine oil will be
lost if the crankcase drain is opened.
1