Measuring Oil Clearance - Yanmar BY Series Service Manual

Cylinder Block and Crankshaft
Figure 5-105
Note: Main bearing caps 1 - 5 are marked on
the exhaust side.
All bearing caps must be installed in their
original locations.
6BY Engines: Main bearing caps No. 6
and 7 are not marked, but No. 6 is the
location of the thrust bearing
(Figure 5-105).
Figure 5-106
12. Remove the crankshaft bearing caps and main
bearing inserts (Figure 5-106).
13. Remove crankshaft. Inspect and measure
crankshaft journals as required.
BY Service Manual

Measuring Oil Clearance

Oil clearance should be checked during
disassembly to determine the extent of wear, and
during reassembly to ensure long engine life. The
same procedure is done for both connecting rods
and main bearings.
1. Remove the bearing cap. Do not remove the
bearing inserts at this time.
2. Wipe oil from the bearing insert and crankshaft
journal surfaces.
Figure 5-107
3. Place a piece of PLASTIGAGE
(Figure 5-107, (1)) along the full width of the
bearing insert.
IMPORTANT
Do not rotate crankshaft when using
PLASTIGAGE. A false reading may result.
4. Install the bearing cap using the old bolts and
tighten to specification. See Special Torque
Chart on page 5-11.
5. Remove the bearing cap.
ENGINE
(1)
0001898
®
5-63