Piston Installation - Mercury 40 Service Manual

2. Install the second and top compression rings ("T" side up). Spread rings just enough to
slip over piston.
a -
b -
c -

Piston Installation

1. Align piston ring end gaps as shown.
a -
b -
c -
d -
NOTE: Cylinder bores must be clean before installing pistons. Clean with light honing, as
necessary. After honing, clean cylinder bores with water and detergent. After cleaning, swab
cylinder bores several times with engine oil and a clean cloth, then wipe with a clean dry
cloth.
90-828631R3 MARCH 1999
c
Top Compression Ring ( "T" Side Up)
Second Compression Ring ( "T" Side Up)
Install Side of Ring Stamped "T" Towards Top of Piston
c
a
End Gap – Top Compression Ring
End Gap – Second Compression Ring
End Gap – Upper Oil Ring Rail (Align with Locating Pin)
End Gap – Lower Oil Ring Rail
a
b
53818
UP
b
d
CYLINDER BLOCK/CRANKCASE
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