Doosan DX60R Shop Manual page 327

Inspection of Idler Gear and Shaft
1. Measure the outside diameter (1, Figure 207) of the idler
gear shaft (2, Figure 207). See "Idler Gear Shaft and
Bushing" on page -97 for specifications.
2. Measure the inside diameter (3, Figure 207) of the idler
gear bushing (4, Figure 207) See "Idler Gear Shaft and
Bushing" on page -97 for specifications.
Honing and Boring
Pistons must move freely in the cylinders while maintaining
adequate compression and oil sealing. If the cylinder walls are
scuffed, scored, out-of-round, or tapered beyond specifications,
rebore and hone to restore cylinders to usable condition. Slight
imperfections can be corrected by honing alone.
1. Boring - Significant cylinder damage may be corrected by
boring the cylinder to an oversize dimension. Refer to the
appropriate parts catalog for available oversize pistons
and piston rings.
• Boring a cylinder should always be done in a
properly equipped machine shop.
• A bored cylinder should always be finished with a
hone to properly prepare the cylinder surface so the
new piston rings will seat properly.
• After the cylinder has been bored and honed, install
the appropriate oversize pistons and piston rings.
2. Honing - Minor cylinder imperfections may be corrected
by using a rigid cylinder hone (1, Figure 208). Be sure not
to exceed the maximum cylinder bore specification.
Deglazing - A used cylinder that did not require boring or
honing, should always be deglazed with a ball hone (2,
Figure 208) before installing new piston rings. This will
properly prepare the cylinder surface to allow new piston
rings to seat properly.
Engine
1
2
Figure 207
Figure 208
4
3
FG008955
SP001693
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