Rotax 912-UL Repair Manual

PlaccO-ring87x2 on cylinder
throat and
oil cylinder
wall.
Pay attention topositionof
pistonringjoint.
Jointof
1"
and 3dring
should
bein
middleof
piston
skirt and mid-ring
180o
staggered,
ring-joint
must
never
be
in area of
piston pin
boss. Oil
piston
and
carefully
fit respective
cylinder
over
piston,
utilizing
piston
ring clamp.
Same
procedure
on other cylinders.
IATTENTION:
To
prevent
ring
breakage, use
1
pistonringclamp
2
.
without
fail!
g
Oil
tappet
bores
on crankcase and
apply
MOLYKOTE G-N
paste
to
hydraulic tappets and
install
them
in
respective
order, but
on
one side
only,
to
prevent
dropping out
when
turning engine over.
7.3) Cylinder
head
Apply
a thin
film
of
LOCfifEzzl
to sealing
face
ofcylinder.
Install respective
pushrod
O
in
both
retum
tubes on
pre-assembled
cylinder
head
and
place pre-oiled
O-ring O
16x5
on
return
tube
CI.
Mount
cylinder
head
until O-rings
I on
oil
return
tutres 0
rest in
crankcase
O.
Now lift cylinder
@ to
engage centering @ of
head
O to cylin-
der
without
jamming
and subsequent
leakage.
Tighten cylinder
head
crosswise
with 2
cap
nuts
M8 and
2 hex. nuts M8
along
with
washers.
Tightening slightly
only!
Pay attention for squeezing O-ring
evenly
into
crankcase O.
Repeat same
procedure
on
nextcyl-
inder head.
nlng end
gap

Rotax 912-UL Specifications

General

Displacement	1211 cc
Bore x Stroke	79.5 mm x 61 mm
Compression Ratio	9.0:1
TBO (Time Between Overhaul)	2000 hours
Engine Type	4-cylinder, 4-stroke
Power Output	80 hp
Cooling System	Liquid/air-cooled
Fuel Type	Avgas 100LL or unleaded automotive gasoline
Oil Capacity	3 liters
Fuel System	2 carburetors
Oil System	Dry sump forced lubrication with separate oil tank
Reduction Gear Ratio	2.43:1
Max Continuous Power	75 hp (56 kW)