Effectivity: 912 i Series
Edition 1/Rev. 0
d0
593
5.
fm
MAINTENANCE MANUAL
BRP-Powertrain
72-30-10
Page 8
July 01/2012
PISTON RINGS - INSPECTION
Fig. 7
PISTON PIN - INSPECTION
Fig. 8
CYLINDER - INSPECTION
NOTE:
If the sealing surface of the cylinder has
slight carbon residues. This is a sign of
leaking. The cylinder must be touched
up with the cylinder head until uniform
contact is achieved.
Step
Procedure
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, cle-
an 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).
NOTE:
Examine the ring surface clo-
sely to identify the supporting
part and thus also the wear
which has already taken pla-
ce.
1. Cylinders
2. Piston ring
3. Feeler gauge
m
WARNUNG
NOTICE
The mono hook circlips for the axial piston pin
circlip must only be used once and must there-
fore be replaced.
Step
Procedure
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 wi-
thin tolerable dimensions, the
piston pin must be replaced.
2
Measure dimension PI03. See also secti-
on 72-30-10 Wear limits.
m
WARNUNG
NOTICE
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.
Summary of Contents for Rotax 912 i Series
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