Hydraulic Governor Disassembly - Rotax 912 Series Maintenance Manual

14.4.8)
2
fig. 139
00256
4
4
7
8
16
14
13
15
Effectivity: 912 Series
AIRCRAFT ENGINES
MAINTENANCE MANUAL II

Hydraulic governor disassembly

See fig.139 and 140.
Remove banjo bolts M10x1 Q and sealing rings W on
both sides from governor flange E and oil pump housing
1
and detach oil line. Remove the 4 Allen screws M6x20
R and the two Allen screws M6x16 T securing oil inlet
flange. Remove governor flange with O-ring 32x4 placed
behind and spacer.
After removal of propeller gearbox the drive can be
disassembled. Fix drive sleeve Y with holder 242 660.
3
Remove Allen screw M8x16 U and vacuum pump gear
I with drive sleeve O. Remove countersunk screw P
M5x12 with washer for ball bearing fixation.
4
Press out needle bearing { and ball bearing } with
suitable step punch towards gearbox.
NOTE:
4
5
5
12
10
00257
If service work is necessary on the propeller governor, it must be sent to
the engine manufacturer.
Needle bearing and ball bearing are dam
aged by this procedure and must be
replaced.
Check inner diameter q of propeller shaft and
journal w of oil inlet flange. The wear will
probably show as a flat area on the journal.
Check teeth of drive gear and vacuum pump
gear I. Visually check ball bearing } and
roller bearing r.
CAUTION: The fixation
screw U M8 for vacuum pump
gear is for propeller governor
11
drive 16 mm long (.63 in.) and
9
has a thin screw head. For
vacuum pump drive, however,
it is only 14 mm long (.55 in.)
with standard screw head.
Clean parts carefully and re-
move sealant residues. Check
sealing surface and all oil bores
in governor flange E for free
passage. Visually check nee-
dle bearing { as well as teeth
and bearing surface of drive
sleeve O. Care for clean con-
necting surface for oil pres-
fig. 140
sure hose.
page 92
Initial issue, Jan. 01/2002