Porsche 928 Workshop Manual page 130

13
Engine. Crankshaft, Pistons
928
CHECKING CRANKSHAFT BEARING CLEARANCE
The "Plastigage" method is a simple way of
checking bearing clearance.
Plastigage is available in three different sizes
for measuring ranges from 0.025 to 0.23 mm.
TYP=
FG-1
PR-1
PB-1
Color
green
red
blue
Measuring Range
L,
0.025 to 0.075 mm
0.05 to 0.15 mm
;
0.10 to 0.23 mm
Checking Radial Clearance
Checking End Play
1. Remove crankcase lower section.
2. Remove oil from bearing shell and bearing
journal.
Use Special Tool VW 381 to check end play.
Play of new bearings:
0.110 to 0.312 mm
Wear limit:
0.40 mm
3. Place Plastigage having width of bearing on
crankshaft journal in axial direction. Install
crankcase lower section carefully and tighten
to specified torque.
Note
Do not turn crankshaft while measuring.
4. Remove crankcase lower section. Read wiuth
of flattened Plastigage from measuring scale.
Corresponding value on measuring scale equals
the bearing clearance.
Play of new bearings:
0.020 to 0.098 mm
Wear limit:
0.16 mm
13 - 8
Checking Crankshaft Bearing Clearance Printed in Germany