3. TROUBLESHOOTING
53
②
Piston check
Check the piston and cylinder for contacting, and check the groove for defects, piston top for
burn and cracks. If damaged, replace.
Clean the carbon deposit
Clean the deposit round the piston top and cylinder neck before checking, first soak the
carbon deposit with kerosene, and then clean with meter scraper or metal brush.
a)
Piston skirt O.D
Measure the piston skirt O.D with outside micrometer, if out of the
service limit, replace it.
Type
Standard
Service Limit
R2200/R2800
67.985mm
67.845 mm
R3000
69.985mm
69.975 mm
b) Piston pin bore to piston clearance
Separately measure the piston pin bore I.D and O.D with inside micrometer and outside
micrometer. Then calculate clearance by measuring results.
c) Piston-cylinder clearance
Difference between cylinder maximum diameter and piston skirt should be considered as
piston-cylinder clearance.
Standard
Service Limit
0.002-0.014mm
0.06mm
