Doosan DX60R Shop Manual page 312

Measuring Idler Gear-to-Crankshaft Gear Backlash
1. Install a dial indicator as shown in Figure 170.
2. Rotate the idler gear back and forth to check the idler
gear-to-crankshaft gear backlash. The total indicator
reading is the backlash. Record the measurement.
Measuring Idler Gear-to-Camshaft Gear Backlash
1. Drive a small wooden wedge between the crankshaft gear
and idler gear to prevent the idler gear from rotating.
2. Install the dial indicator to read the camshaft gear
backlash. Rotate the camshaft drive gear against the idler
gear to measure the backlash. Record the measurement.
3. Check the idler gear-to-fuel injection pump drive gear
backlash in the same manner as the camshaft drive gear.
Record the measurement.
Removal of Timing Gears
1. Remove the bolts from the idler gear shaft (1, Figure 171).
Remove the idler gear shaft, idler gear (2, Figure 171) and
bushing (3, Figure 171).
2. Do not remove the crankshaft gear unless it is damaged
and requires replacement. If the gear must be removed,
remove it using a gear puller.
3. Removal of the camshaft gear requires the camshaft be
removed and placed in a press. Do not remove the
camshaft gear unless it or the camshaft is damaged and
requires replacement. See "Removal of Camshaft" on
page -134
Do not loosen or remove the four bolts retaining the
fuel injection pump drive gear to the fuel injection
pump hub. Do not disassemble the fuel injection pump
drive gear from the hub. Correct fuel injection timing
will be very difficult or impossible to achieve.
4. Do not remove the fuel injection pump drive gear unless
absolutely necessary to avoid damage to the gear or
pump. Do not loosen or remove the four bolts (3, Figure
172) retaining the pump drive gear to the hub. Only
remove the nut (1, Figure 172) and washer (2, Figure 172),
leaving the hub attached to the gear. Remove the pump
drive gear and hub as an assembly using a gear puller.
Engine
Page 132
CAUTION
Figure 170
Figure 171
Figure 172
SP001693