Suzuki DF 40 Service Manual page 195

If measurement exceeds service limit, replace crankshaft
thrust bearing.
Crankshaft thrust bearing thickness
Standard : 2.470 – 2.520 mm (0.0972 – 0.0992 in.)
Out - of - round and taper (uneven wear) of journals
An unevenly worn crankshaft journal shows up as a differ-
ence in diameter at a cross section or along its length (or
both).
This difference, if any, is determined by taking micrometer
readings.
If any journal is badly damaged or if measurements exceed
service limit, replace crankshaft.
09900-20202 : Micrometer
Out - of - round : A – B
Taper : a – b
Out - of - round and taper
Service limit : 0.01 mm (0.0004 in.)
Crankshaft journal outside diameter
Standard : 44.982 – 45.000 mm (1.7709 – 1.7717 in.)
POWER UNIT 6-52
1. Thrust bearing
A
a b
B
1