Jabiru J450 Constructors Manual
Pre-Paint>Fuselage>Firewall forward>Fit propeller flange extension
Tuesday, April 6, 2010
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Pre-Paint>Fuselage>Firewall forward>Fit propeller flange extension
Objectives of this task:
To remove the universal propeller flange that is shipped with the engine and fit the model-
specific propeller flange extension to the crankshaft. While this is a straightforward
mechanical task it is most definitely a
critical
task and care must be taken.
The universal propeller flange is lock wired in place, however the depth of the propeller
flange extension makes the use of lock wire almost impossible and so we use a strong Loctite
to keep the flange securely fitted. This means that the cleanliness of all threads is critical.
This task will require 2 people: 1 to stop the crankshaft from moving and 1 to loosen and later
tighten the cap screws. This task is intended to be performed by the kit builder with the engine
mounted to the aircraft. In the factory we do this task while the engine is fitted to a mobile
engine stand so some of the photos will be slightly different to what the kit builder could
expect to see.
Materials and equipment required:
Loctite 620 and lockwire
Thread cleaner – Loctite 7471 or Acetone
5/16” Hex drive socket, or alternately a 5/16” Allen key cut straight and fitted to a 5/16”
socket
Torque wrench, set to 30 ft/lbs or 40 Nm
Remove the universal flange
The universal flange is held in place by 6 x 3/8” UNF Allen head cap screws, all of which will
be reused.
Cut and remove the lock wire from the 6 cap screws, then heat the cap screws with a heat gun
in order to loosen the Loctite.
Lock the engine from turning by holding a large blade screwdriver in the ring gear teeth
between the starter motor and the adjacent alloy block (circled in the photo above right).
Crack each cap screw in turn to break the Loctite seal and remove each cap screw and the
related washer.
Set the cap screws and washers aside for later use.
Remove the flange and discard.