Doosan GL08K, Operation & Maintenance Manual

Page: 77 / 206

Maintenance - 71 -
b) Wear measuring

With an outside micrometer
measure the diameter of the
crankshaft journals and pins in the
directions as shown, and compare
the measured values to determine
the amount of wear.

If the amount of wear is beyond the
limit, have the crankshaft ground
and install undersize bearings.
However, if the amount of wear is
within the limit, you can correct the
wear using an oil stone or oiled
grinding paper of fine grain size.
(Be sure to use grinding paper
which has been immersed in oil.)

In case that pin's wear is more
than the limit value, grind the
crankshaft journal and crank pin,
and use the undersized bearings.
CAUTION :
Be sure to use grinding paper which
has been immersed in oil.
<Undersize bearings available>
- Standard
- 0.25 (Inside diameter is 0.25 mm lesser than the standard size.)
- 0.50 (Inside diameter is 0.50 mm lesser than the standard size.)
- 0.75 (Inside diameter is 0.75 mm lesser than the standard size.)
- 1.00 (Inside diameter is 1.00 mm lesser than the standard size.)
There are four sizes of under-size bearings for main bearings and two sizes for connecting rod
bearings. The crankshaft can be re-machined to fit in these under-size bearings.
EAMD057I
B B
B
A
A
B
EFM2047I
Standard Limit
Journal
diameter
83.966 ~
83.988 mm
83.466
mm
Pin
diameter
70.971 ~
70.990 mm
69.971
mm
" R "
" R "
" R " " R "
EFM2048I
" R "
Normal Poor Poor