Doosan DX60R Shop Manual page 297

Squareness
Use a flat surface and a square to check each spring for
squareness (Figure 145). See "Valve Spring" on page -96 for
the service limit.
Free Length
Use a caliper to measure the length of the spring (Figure 146).
See "Valve Spring" on page -96 for the service limit.
Inspection of Valve Bridges
Visually inspect the contact surface at both ends of the valve
bridge (2, Figure 147) for excessive wear or mushrooming.
Remove and inspect the seat (1, Figure 147).
Measure the diameter of the valve bridge guide pin bore in the
valve bridge and guide pin (3, Figure 147). See "Rocker Arm
and Shaft" on page -96 for the service limit.
Reassembly of Cylinder Head
Use new gaskets, O-rings, and seals on reassembly of the
cylinder head.
Liberally oil all components during reassembly to prevent
premature wear or damage.
Engine
IMPORTANT
Figure 145
Figure 146
Figure 147
SP001693
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