SERVICE MANUAL
CONNECTING RODS, PISTONS, RINGS & SLEEVES
Section 5
8.
Check the side clearance of each oil
regulating ring in its respective groove.
a.
Refer to “SPECIFICATIONS” for proper
clearance.
b.
On a used piston, it will probably be found
that the side clearances tend to increase
toward the top of the piston due to the
greater operating temperature prevalent at
this point.
9.
Inspect the “windows” of the oil regulating
rings for blocked oilways.
NOTE: Failure to keep the oilways clear will result in
uneven lubrication of the piston and sleeve.
10. All rings must fit loosely in the piston ring
grooves without binding.
11. Ring bearing surfaces must be of a
smooth/satin like finish with no burrs.
Visually inspect new
rings,
prior
to
installation, for burrs.
NOTE: When new rings are being installed on a
used piston for operation in a used sleeve, wear on
the sleeve may have left a ridge where the piston
reaches the top of its stroke. This ridge will cause
noisy engine operation and breakage of the top ring.
Remedy this by removing the ridge before installing
the piston ring.
Clean Cylinder Sleeves as follows:
1.
Using a non-caustic soap solution clean the cylinder
sleeves with minimally abrasive brush.
2.
Thoroughly clean the “O” ring groove in the sleeves.
3.
Dry the sleeves with compressed air.
4.
Clean and flush out the water jacket in the
crankcase.
Inspect Cylinder Sleeves as follows:
1.
Measure the I.D. of the sleeve with an inside
micrometer or bore gauge from the top and bottom
of the sleeve where it is subjected to piston and ring
travel, and the “O” ring area.
a.
Take measurements at right angles to determine
if the sleeve is out of round or excessively
tapered.
b.
Maximum permissible diameter sleeve
wear, at top of ring travel, before
replacement is 0.10 mm (0.004 in.).
c.
If sleeve does not meet specifications, it
must be replaced with a new sleeve (and
piston).
2.
Inspect the sleeve for SCUFFING or
SCORING. Replace sleeve (and piston) if
this condition is found.
NOTE: Do not hone the cylinder sleeves.
3.
Inspect
Counterbore
for
BURRS
or
FRACTURES.
If Sleeve Replacement is Required;
4.
Identify between Hardened and Unhardened
cylinder sleeves as follows:
a.
Make a solution known as NITAL by adding 10
parts of nitric acid to 90 parts of alcohol (rubbing
alcohol is satisfactory).
CAUTION! Add the nitric acid to the alcohol.
Do not add alcohol to the nitric acid.
b.
Rub the I.D. of the sleeve near the top or near
the bottom with the Nital. The etched area
should extend into the sleeve approximately 1/2
inch and need be no more than 1/2 inch wide.
CGES-185-3
PRINTED IN UNITED STATES OF AMERICA
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