How to Install the Timing Gear of Isuzu Engine (4JH1 type)
1. Install the crankshaft gear.
a. Install the crankshaft gear. b. Use the crankshaft gear installer (1) to install the crankshaft
gear (2).
mark (".-") must be facing outward.
Special tool:
 Crankshaft Gear Installer: 9-8522-0020-021 2
LNWC1BSH007001
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2. Install the camshaft timing gear.
a. Install the thrust plate to the cylinder body.
b. Tighten the thrust plate bolts to the specified torque.
Tightening torque:
19 Nm (1.9 kg-m/14 Ib-ft)
c. the camshaft timing gear to the camshaft.
The timing gear mark (":-:") must be facing outward.
d. Install the cam angle rotor to the camshaft timing gear.
The identification mark must be facing outward
. gear to the specified torque.
Tightening torque:
110 Nm (11.2 kg-m/81 Ib-ft)

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3. Install the fuel supply pump.
Refer to "Fuel Supply Pump" in Section 6C, Engine Fuel.
4. Install the idle gear.
a. Apply engine oil to the idler gear and the idler gear shaft.
The idler gear shaft oil hole must be facing up.

b. Position the idler gear setting marks "."and ":"
so that they are facing the front of the engine.
c. Align the idler gear "."setting mark with the crankshaft timing gear (1)".-." setting mark.
d. Align the idler gear ":"setting mark with the camshaft timing gear (2) ":-:"setting mark.
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e. Install the thrust collar and bolts to the cylinder body through the shaft.
   The thrust collar oil hole must be facing up, and the thrust collar chamfered must be outward.
f. Tighten the idler gear bolt to the specified torque.
    Tightening torque: 19 Nm (1.9 kg-m/14 Ib-ft)
5. Install the idle gear.
  a. Apply engine oil to the idler gear and the idler gear shaft.
  b. Align the idler gear B (3) ":"setting mark with the idler gear A (4)":-:"setting mark.
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c. Tighten the idler gear bolt to the specified torque.
Tightening torque: 76 Nm (7.7 kg-m/56 lb-ft)
6. Install the timing gear case cover.
a. Align the gear case with the timing gear case knock pin and then install the timing gear case cover.
b. Tighten the gear case cover bolts to the specified torque.
Tightening torque : 22 Nm (2.2 kg-m/16 lb-ft)

7. Install the crankshaft damper pulley Tighten the crankshaft damper pulley bolt to the specified torque.
NOTE: Hold the flywheel ring gear stationary to prevent the crankshaft from turning when tightening the damper pulley.
Tightening torque:
294 Nm (30 kg-m/217 Ib-ft)