Inspection and Reconditioning (Rev 1/97)
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Timing Gears
1. Inspect the timing gears for chipped or excessively
worn teeth, and for any cracks on or between the teeth.
The gear lash should have been checked during the dis-
assembly of the engine. If not, check the gear lash dur-
ing the assembly of the engine.
NOTE: The camshaft, crankshaft, and injection
pump gears use a press fit. To remove these gears use
a standard gear puller or a hydraulic press. Install
these gears with a hydraulic press.
2. Measure the inside diameter of the idler gear bushing.
The standard dimensions are .7874-.7882 in. (20.000-
20.021 mm). The wear limit is .7906 in. (20.080 mm).
If the idler gear bushing is larger than the wear limit or
is significantly damaged, replace the idler gear bushing.
To replace the bushing, press the old bushing out of the
idler gear and press the new bushing into the idler gear.
Measuring Idler Gear Bushing
3. Measure the outside diameter of the idler gear shaft.
The standard dimensions are .7858-.7866 in. (19.959-
19.980 mm). The wear limit is .7846 in. (19.930 mm).
If the idler gear shaft is smaller than the wear limit or is
significantly damaged, replace the idler gear shaft.
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Measuring Idler Gear Shaft
Camshaft
1. Check the camshaft journals, the cam lobes, the thrust
plate, and the camshaft gear for wear or damage.
2. Measure the camshaft journals. If any of the camshaft
journals are smaller than the wear limit (refer to Speci-
fications) or significantly damaged, replace the cam-
shaft.
Measuring Camshaft Journals
3. Measure the cam lobes. If any of the cam lobes are
smaller than the wear limit (refer to Specifications) or
significantly damaged, replace the camshaft.
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