Perkins 103-06 - Piston, Rings, and Gudgeon Pin Inspection

New standard bore Allowable limit New standard bore Allowable limit
72.49-72.505mm 72.7mm 76-76.019mm 76.2mm
(2.8539-2.8545") (2.8621") (2.9921-2.9928") (2.9999")
Second re-bore
0.5mm
Replace
the
block
(.0196")
Piston and piston rings
- Disassembly
New standard bore Allowable limit
A. Remove piston rings using a piston ring tool.
72.99-73.005mm
73.2mm B. Remove the circlip and extract the gudgeon pin.
(2.8736-2.8742") (2.8818")
Replace
the
block
Bore spec 103-10/Perama M30
Standard bore
Allowable limit
75-75.019mm (2.
9527-2.9534")
75.2mm (
2.9606')
PB040
First re-bore
0.5mm
(.0196")
Inspection
A. Piston
New standard bore Allowable limit
75.5-75.519mm (2.
9724-2.9731 ")
75.7mm
(2.9803 )
a. If outer surface of the piston is excessively
damaged (cracked score, burning, etc.),
replace.
b. Piston skirt
Check the larger diameter of the piston skirt
(10mm from bottom), and check inside
diameter (thrust direction) of the cylinder.
Calculate the clearance between the
cylinder and piston. If this clearance is more
than allowable, or piston diameter is less
than allowable limit, replace the piston.
Second
103-09 Piston/Perama M25
re-bore Standard clearance Allowable limit
0.5mm
(.0196") 0.0525-0.0825mm 0.25mm
(.0021-.0033") (.0098")