Jabiru J450 Constructors Manual
Pre-Paint>Fuselage>Firewall forward>Fit engine mount and engine
Tuesday, April 6, 2010
62 of 343
Fit the engine to the engine mount
Fit the female rubbers to the top mounts and the machined spacers and male rubbers to the
bottom mounts – refer to the drawing on the next page for details.
With the rear of the aircraft supported and with the main wheels chocked, lift the engine into
position and fit the rear engine mount plate onto the bottom engine mounts first: you may
need to tilt the engine slightly down at the front to do this. Use AN4-31A bolts fed from the
rear of the mounts with the lock nuts towards the
front.
Lift the front of the engine and fit the top rear engine
mount plate onto the top mounts and fit the male
rubbers, machined washers, flat washers and lock
nuts to both top mounts. Fit the female rubbers, flat
washers and lock nuts to both bottom mounts. Note
that these are
steel
lock nuts and not Nylocs.
It may be necessary to compress the mount rubbers
in order to get the steel lock nuts on: use a “G” clamp
or similar and clamp across a socket on the head of
the bolt and the side of the machined washer beside
the steel lock nut, as shown at right. The clamping points have been circled in yellow.
Torque each of the 4 steel lock nuts to 11 Nm (8 foot pounds).
Level the aircraft
For the next step the aircraft must be absolutely level in both the lateral (rolling) and
longitudinal (pitching) planes.
Lateral plane
: place a 3” block on the top of each front wing mounting lug and place a spirit
level or a digital protractor across the top of the cabin so that it rests on both blocks. Pack the
main wheels as required to level the aircraft.
Longitudinal plane
: the objective is to level the fuselage along the “waterline” – the line of
the join between the upper and lower sections of the fuselage. Use a spirit level or a digital
protractor and pack under the nose wheel or empennage until the waterline is level.
Once the aircraft is satisfactorily levelled make sure it stays that way: chock the wheels and
consider lashing the empennage to the packing with a tie-down strap.