Crankshaft Bearings; Timing Gears - Toro Groundsmaster 300 Series Service Manual

Crankshaft Bearings (Fig. 68, 69)
1. Measure the crankshaft for "run-out" (bend). Mount
the crankshaft in a pair of V-blocks (or live centers) and
use a dial indicator to measure the run-out in the crank-
shaft. The maximum allowable crankshaft run-out is
.0012 inch (0.03 mm).
2. Check the crank journals and crank pins for damage
such as galling, seizure, etc. If journals or pins are
seriously damaged they may be reground and over-
sized bearings installed. The main bearing and connect-
ing rod bearing oil clearances may be measured with a
micrometer or Plastigauge. Crankshaft oil clearances
are: Journal, 0.0039 inch (0.10 mm); Crank pin, 0.0059
inch (0.15 mm).
NOTE: When using Plastigauge to measure the clear-
ance between the crankshaft and its bearings, install the
crankshaft into the cylinder block, place a piece of
Plastigauge onto the crank pin or journal, and torque the
bearing cap (with bearing) in place.
CRANKSHAFT WHEN PLASTIGAUGE IS IN PLACE SINCE
THE PLASTIGAUGE WOULD BE DESTROYED
the bearing cap and measure the width of the Plasti-
gauge to determine the clearance. If the oil clearances
exceed these amounts attempt to install a new bearing
to reduce the clearance. If installing a replacement
bearing does not reduce the clearance to within toler-
ance the crankshaft must be reground and an oversized
bearing installed.
Timing Gears (Fig. 70)
1. Inspect the idler gear, fuel injection pump gear, cam-
shaft gear and crankshaft gear for wear or damage.
Replace these gears if defective.
Cylinder Block Overhaul
DO NOT TURN THE
. Remove
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Figure 68
Figure 69
Figure 70
®
Groundsmaster 300 Series