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Other than checking the prop flange according to the specifications listed in the Jabiru 3300 engine manual..
Engine Overhaul Manual Jabiru Aircraft Pty Ltd
JEM0001-22 Jabiru 2200 & 3300 Aircraft Engines
Page 22 and top of 23 for high power strike as defined 3.4.2
184.108.40.206 Low Power Prop Strike Checklist
• The flywheel retaining cap screws (6) and propeller flange retaining screws (6) need to be replaced
after any prop strike.
• If a low power strike has been encountered then crankshaft runout must be checked as detailed in
Section 4.4.1 and if necessary the propeller flange and/or the crankshaft may need to be replaced.
• When replacing the flywheel and propeller flange cap screws remember that they are held in place with
Loctite 620, which is very strong. They will be very difficult to undo and great care must be taken not to
break any of them. Lock the crankshaft from turning and then apply heat to the area around the cap
screws, and then try to crack each cap screw loose using an Allen key and a 3/8” breaker bar. This step
may involve heating the end of the crankshaft several times until you can safely undo each cap screw.
Details on removing these screws are included in Section 4.5.4. The procedure to be used for replacing
the screws in the propeller flange is the same.
• Do NOT apply heat directly to the cap screws because this could weaken the screw material, but rather
apply the heat to the area around the cap screws. This is particularly important because you will need to
apply considerable turning force to undo each cap screw.
I had a prop tracking issue one time that was the result of two bolts between the prop flange and crankshaft that were never tightened by the original builder, but had been loctited. The washers was loose and able to slide around! I bought new Unbrako bolts and installed them without loctite and torqued each in sequence to just under final torque. Then removed one at a time applied the loctite and torqued to final specifications before moving to the next bolt. Prop tracking issue gone!
Most important to obtain an even clamping load on all parts before any thread locking compound sets up!