Rotax MMH-912 Series Maintenance Manual page 96

■ CAUTION: The value can be positive or negative.
(I) For smoother removal of the piston stopper turn the piston slightely away from
the piston stopper.
(J) Repeat this procedure for cylinder 3. The piston will be stopped at 180°.
(K) Read the difference to 180° from the protractor.
■ CAUTION:
(L) Repeat this procedure for cylinder 4. The piston will be stopped at 180°.
(M) Read the difference to 180° from the protractor.
■ CAUTION:
■ CAUTION: If a value exceeds the GB20 limit, then the engine needs to be
■ CAUTION: The deviation of the crank pin (as a whole) must not exceed the
Example showing the results from meassuring a crankshaft, where the GB20
threshold is not exceeded:
Cylinder
1
2
3
4
Effectivity 912/914 Series
Edition 1 / Rev. 3
BRP-Powertrain
Maintenance Manual
The value can be positive or negative.
The value can be positive or negative.
overhauled by a ROTAX-authorised service partner.
GB20 value. For GB20 see also Chapter 4 "wear limits".
deviation
0°
+ 2°
0°
+1°
Fig. 72-21/3
08690
72-00-00
page 24B
October 01/2010