DSG-423 GENERAL INFORMATION
01-27
Piston Selection
NOTE: The cylinder bore must be within the
specifications for taper and out-of-round before fitting a
piston.
1. Select a piston size based on the cylinder bore.
NOTE: For precision fit, new pistons are divided into
three categories within each size range based on their
relative position within the range. A paint spot on the
new pistons indicates the position within the size range.
2. Choose the piston with the proper paint color.
• Red – in the lower third of the size range.
• Blue – in the middle third of the size range.
• Yellow – in the upper third of the size range.
Piston Ring End Gap
CAUTION: Use care when fitting piston rings to
avoid possible damage to the piston ring or the cyl-
inder bore.
CAUTION: Piston rings should not be transferred
from one piston to another to prevent damage to
cylinder worn or piston.
NOTE: Cylinder bore must be within specification for
taper and out-of-round to fit piston rings.
1. Use a piston without rings to push a piston ring in a
cylinder to the bottom of ring travel.
2. Use a feeler gauge to measure the top piston ring
end gap and the second piston ring end gap.
Special Tool(s)
Feeler Gauge
D81L-4201-A or Equivalent
Special Service Tools called for
by the procedures can be
obtained by calling:
1-800-ROTUNDA
(1-800-768-8632)