Crankshaft Alignment - Polaris Magnum 2x4 Service Manual

Crankshaft Alignment
ENGINE
EC25PF/EC28PF Engines
When the crankshaft runout exceeds .005" (.15 mm) it must be straightened or replaced. To straighten a crank-
shaft the crank wheel(s) must be relocated on the lower rod pin. The four basic movements which may be required
to realign the crankshaft are listed below.
1. If the dial indicators are moving in the same
direction and approximately the same amount
while the shaft is rotated, the crankshaft has
twisted on the lower rod pin. To correct this,
remove the shaft from the fixture and strike the
crank wheel on the high spot (A). This will rotate
the wheel on the lower rod pin.
2. If the right side indicator is moving more than the
left indicator while turning the shaft, and the high
spot is found with the rod in this position (see photo
at right), the crankshaft wheels will have to be
squeezed together. Remove the shaft from the
fixture. Locate the high spot and squeeze directly
opposite from it using a large channel lock pliers or
a vise. Arrows show direction of force to be
applied.
3. If the right side indicator is moving more than the
left indicator while turning the shaft, and the high
spot is found with the rod in this position (see photo
at right), the crankshaft wheels will have to be
spread apart. Place a large chisel between the
wheels and force the chisel downward. This will
open the wheels and bring the end of the shaft
down (8). Arrows show the direction of force to be
applied.
4. If the indicators are moving in opposite directions while turning the shaft, the shaft is twisted. To correct this,
remove the shaft from the fixture and strike the high spot found on the left side indicator.
NOTE: Squeezing the crank wheels is always done opposite the high spot. Spreading the crank wheels is always
done at the high spot. Twisting the crank wheel by striking it is always done at a right angle to the lower rod pin,
and at the high spot.
Polaris Industries Inc.
3.13
7/96