Polaris 600 EDGE RMK, Service Manual

Page: 121 / 392

ENGINES
3.58
Crankshaft Indexing
Polaris crankshafts are pressed together or ‘‘indexed” so
the connecting rod journal center lines are 180 ° (twins) or
120 ° (triples) apart from each other.
It is sometimes necessary to check multi-cylinder crank-
shafts to verify that one cylinder has not been forced out
of position relative to the other cylinder or cylinders.
Causes for out-of-index crankshafts include but are not
not limited to:
S
Hydrolock from water or fuel;
S
Impact to drive clutch from foreign object or acci-
dent;
S
Abrupt piston or other mechanical failure;
S
Engine lock-up due to drive belt failure;
Following is a method of checking:
CAUTION:
Disconnect battery ground cable and all spark plug high
tension leads; ground high tension leads to engine. Dis-
connect lanyard from engine stop switch before proceed-
ing with the following steps.
1. Securely fasten a degree wheel on the
flywheel or PTO end of crankshaft. Use a
large degree wheel for more accuracy, and
make sure it is mounted concentrically with the
crankshaft center line.
2. Sharpen a coat hanger or section of welding
rod and anchor it to a convenient spot. Point
the sharpened end at the outer perimeter of
the degree wheel.
3. Install a dial indicator into the magneto end
cylinder spark plug hole (front) (#1). (The
ignition timing is referenced by the magneto
end.)
4. Rotate the engine to bring the piston to top
dead center (TDC) on the cylinder with the
indicator installed.
5. Locate TDC as accurately as possible by
finding the center of the point where there is no
piston movement. ‘‘Zero” the dial indicator at
this point. Continue to rotate the crankshaft in the
normal direction of rotation until the dial indicator
reads .100 ² (2.54mm) after top dead center (ATDC).
IMPORTANT: Do not allow the crankshaft to move
from this position.
Dial Indicator
Degree
Wheel
.100 ATDC