Onan MJA Series Service Manual page 87

at
3.9 Enqine
·D'isassembly
If
engine disassembly is necessary, observe the following order
(i.
e.
FlywheeL Gear Cover ...
J.
As disassembly progresses, the order
may be changed somewhat as will be self-evident.
The engine assembly procedure is the reverse of disassembly. Any
special assembly instructions for a particular component are included
in the applicable section. When reassembling check each section for
these special assembly instructions or procedures.
3.9.1 FLYWHEEL
l\' i
Remove the flywheel guard. The flywheel is a tapered
fit
on the crank­
shaft. . Remove the flywheel mounting screw. Remove the 2 capscrews
J
holding the pulley and remove the pulley. Replace the flywheel mountin
screw part way and install the pulley over the screw. Tighten the pulle
will contract rapidly and may FIG 3.9.A - PULLING FLYWHEEL
shrink to the flywheel before it
~
is in place.
If
this occurs, a new ring gear may be. required.
3.9.2 GEAR COVER
To remove
the
gear cover, detach the governor ball joint and remove
the ignition breaker points (start-disconnect switch), plate and gear.
Remove the water pump connections. Remove the screws holding
the
gear COVer to the crankcase. To loosen the gear cover, tap itwith a
soft hammer. . .
capscrews to pull the flywheel.
3.9.1.1 Ring Gear. - To remove
the ring gear,
if
damaged, s:?w
part way through, then break
it
using a cold chisel and heavy
hammer.
To install a new ring gear, place
it in an oven heated to 380 - 400
0
F for 30 to 40 minutes. CAUTION:
DON'T HEAT WITH A TORCH!
When heated properly, the ring
will fall into place on the flywheel.
If it
doesn't go on
all
the way by
itself, drive it into place with a
hammer.
Do it
fast and don't
damage the gear teeth. The ring
TIGHTEN
PULLEY
SCREWS
TO
LOOSEN
FLYWHEEL
I
~.