Rotax 912 i Series Maintenance Manual page 216

PISTON RINGS - INSPECTION
Step
1 Check the cleaned piston rings for piston
ring joint clearance.
NOTE: To determine the piston ring joint
clearance, remove the piston
rings with piston ring pliers,
clean them and place them in
the cylinder.
Aligned with a piston in the cylin-
der and pushed approx. 10 mm
(0.3937 in.) from the upper edge
into the cylinder.
2 Measure the piston ring joint clearance
using a feeler gauge. See also section 72-
30-10 Wear limits (PI07).
Examine the ring surface
NOTE:
closely to identify the sup-
porting part and thus also the
wear which has already ta-
ken place.
Fig. 7
1. Cylinders
3. Feeler gauge
PISTON PIN - INSPECTION
NOTICE
WARNUNG
The mono hook circlips for the axial piston pin
circlip must only be used once and must therefo-
re be replaced.
Effectivity: 912 i Series
Edition 1/Rev. 0
BRP-Powertrain
MAINTENANCE MANUAL
Procedure
2. Piston ring
Step
1 Check the piston pin for traces of wear in
the region of the conrod bearing and in
the region of the piston bearing and mea-
sure it.
NOTE: If perceptible traces of wear are
found, even if the pistons are
within tolerable dimensions, the
piston pin must be replaced.
2 Measure dimension PI03. See also sec-
tion 72-30-10 Wear limits.
Fig. 8
CYLINDER - INSPECTION
NOTICE
WARNUNG
If the engine has been overheated, a hardness
test of the cylinder is necessary. The hardness
test takes place at measurement point CY04.
See also section 72-30-10 Wear limits.
If the sealing surface of the cylinder has
NOTE:
slight carbon residues. This is a sign of
leaking. The cylinder must be touched
up with the cylinder head until uniform
contact is achieved.
Procedure
72-30-10
Page 8
July 01/2012