Polaris TRAIL BOSS 325 2001, Manual

Page: 63 / 296

ENGINE
3.7
CYLINDER HONE SELECTION/HONING PROCEDURE
Selecting a hone which will straighten as well as remove material from the cylinder is very important. Using a
common spring loaded finger type glaze breaker for honing is never advised. Polaris recommends using a rigid
hone or arbor honing machine which also has the capability of oversizing.
Cylinders may be wet or dry honed depending upon the hone manufacturer’s recommendations. Wet honing re-
moves more material faster and leaves a more distinct pattern in the bore.
CAUTION:
HONING TO OVERSIZE
If cylinder wear or damage is excessive, it will be nec-
essary to oversize the cylinder using a new oversize
piston and rings. This may be accomplished by either
boring the cylinder and then finish honing to the final
bore size, or by rough honing followed by finish honing.
For oversize honing always wet hone using honing oil
and a coarse roughing stone. Measure the piston (see
piston measurement) and rough hone to the size of the
piston. Always leave .002 - .003
s
(.05 - .07 mm) for fin-
ish honing. Refer to piston-to-cylinder clearance spec-
ifications on page 3.4 before honing. Complete the siz-
ing with fine grit stones to provide the proper
cross-hatch finish and required piston clearance.
A finished cylinder should have a cross-hatch pattern to ensure piston ring seating and to aid in the retention of
oil during initial break in. Hone cylinder according to hone manufacturer’s instructions, or these guidelines:
S
Use a motor speed of approximately 300-500 RPM, run the hone in and out of the cylinder rapidly until cutting
tension decreases. Remember to keep the hone drive shaft centered (or cylinder centered on arbor) and to
bring the stone approximately 1/2
s
(1.3 cm) beyond the bore at the end of each stroke.
S
Release the hone at regular intervals and inspect the bore to determine if it has been cleared, and to check
piston fit.
IMPORTANT:
CLEANING THE CYLINDER AFTER HONING
It is very important that the cylinder be thoroughly cleaned after honing to remove all grit material. Wash the cylinder
in a solvent, then in hot, soapy water. Pay close attention to areas where the cylinder sleeve meets the aluminum
casting. Use electrical contact cleaner if necessary to clean these areas. Rinse thoroughly, dry with compressed
air, and oil the bore immediately with Polaris Premium 4 Synthetic 0-W40 lubricant.
EXAMPLE OF CROSS HATCH PATTERN