4) Valve Seats - Rotax 912 Series Maintenance Manual

3.11.4) Valve seats

Effectivity 912/914 Series
Edition 1 / Rev. 0
BRP-Rotax
Maintenance Manual
See Fig. 72-66.
Carry out a visual inspection of the valve faces for damage and wear.
Apply engineers blue evenly to the valve faces and fit the valves into the
respective valve guides. Turn the valve under gentle pressure to
produce a clear imprint of the sealing surface on the valve seat ring.
Ensure that the sealing surface of the valve seats (1) is clean and if
necessary, regrind with valve lapping paste.
■ CAUTION:
The annular imprint on the valve face must be a
continuous, unbroken ring.
The width of the imprint corresponds to the width of the
valve seat CH02.
■ CAUTION:
If burned spots or deformation are detected, send the
cylinder head to a ROTAX authorized overhaul facility
for overhaul.
See 72-00-00 sec. 4.
1
45°
CH02
00285
Fig. 72-66
72-00-00
page 63
May 01/2007