Check Main Bearing Clearances - Briggs & Stratton Vanguard 430000 User Manual

Check Main Bearing Clearances

NOTE: If main bearings show signs of flaking or
scoring, bearings must be replaced.
NOTE: Main bearing saddles in cylinder block, main
bearing caps, main bearings, and crankshaft
journals must be clean and free of oil.
1. With upper main bearings installed, install
crankshaft.
2. Lay a strip of plastigage lengthwise on journal
(A, Figure 4).
NOTE: Do not lay plastigage across hole in
crankshaft journal.
Figure 4
3. Assemble main bearing cap with bearing
(Figure 5) and torque to values listed in
Section 14 - Engine Specifications.
NOTE: Do not allow crankshaft to rotate.
Figure 5
4. Remove the bearing cap. Measure the
plastigage at its widest point (A, Figure 6). If
the clearance is not within specification,
replace the bearings.
• Standard Main Bearing Clearance -
0.0008 - 0.0017 in. (0.020 - 0.044 mm)
• Reject Main Bearing Clearance - 0.0028
in. (0.07 mm)
Figure 6
5. Repeat procedure for each main bearing.
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