Use the micrometer to measure at several points around the ring.
Piston Ring Thickness Standard:
Top [A] 0.77 
0.79 mm (0.0303
0.0311 in.)
Second [B] 0.78 
0.79 mm
(0.0307 
0.0311 in.)
Service Limit:
Top 0.70 mm (0.0276 in.)
Second 0.71 mm (0.0280 in.)
If any of the measurements is less than the service limit on either of the rings, replace all the rings.
NOTE
When using new rings in a used piston, check for uneven groove wear. The rings should fit perfectly parallel to the groove sides. If not, replace the piston.
Piston Ring Groove Width Inspection
Piston Ring End Gap InspectionEvaporative Emission Control System (California
model only)
This system routes fuel vapors from
the fuel system into the running engine
or stores the vapors in a canister when
the engine is stopped. Although no adjustments
are required, a thorough visual
inspection must be made at the intervals
specified by the Periodic Maintenance
Chart.
Inspection
...
KIBS Servicing Precautions
There are a number of important precautions that should
be followed servicing the KIBS.
This KIBS is designed to be used with a 12 V sealed battery
as its power source. Do not use any other battery
except for a 12 V sealed battery as a power source.
Do not reverse the battery cable connec ...
Brake Disc Wear Inspection
Measure the thickness of each disc [A] at the point where
it has worn the most.
If the disc has worn past the service limit, replace it.
Measuring Area [B]
Brake Disc Thickness Standard:
Front 5.3 5.7 mm (0.21
0.22 in.)
Rear 4.8 5.2 mm (0.19
0.20 in.)
Service Limit:
Front 5. ...