Kubota WG972-E2 Workshop Manual page 114

WG972-E2, DF972-E2, WSM
Piston
1. Turn the flywheel and bring the piston to top dead center.
2. Draw out the piston upward by lightly tapping it from the bottom
of the crankcase with the grip of a hammer.
3. Draw out the other pistons after the same method as above.
(When reassembling)
• Before inserting the piston into the cylinder, apply enough engine
oil to the piston.
• When inserting the piston into the cylinder, face the mark on the
connecting rod to the fuel camshaft.
• When inserting the piston into the cylinder, place the gap (C) of
the top compression ring on the opposite side of the slant portion
(1), and stagger the gaps (A), (E) of the second compression ring
and spacer making 2.09 rad (120 °) from the gap of the top
compression ring. Further, stagger the gaps (D), (B) of the upper
and lower side rail making 1.57 rad (90 °) from the gap of the
spacer.
■
IMPORTANT
• Do not change the combination of cylinder and piston. Make
sure of the position of each piston by marking. For example,
mark "1" on the No. 1 piston.
• When installing the piston into the cylinder, place the gaps
of all of the piston rings as shown in the figure.
• Carefully insert the piston using a piston ring compressor
(1). Otherwise, their chrome-plated section may be
scratched, causing trouble inside the cylinder.
(1) Piston Ring Compressor
(A) Second Compression Ring Gap
(B) Side Rail Gap
(C) Top Compression Ring Gap
S-44
GASOLINE / LPG ENGINE
(D) Side Rail Gap
(E) Spacer Gap
(a) 2.09 rad (120°)
(b) 1.57 rad (90 °)
W10277450
KiSC issued 01, 2006 A