Jabiru J450 Constructors Manual
Pre-Paint>Fuselage>Firewall forward>Fit ram air cooling ducts
Tuesday, April 6, 2010
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Test fit the ducts
Fitting the ducts will require adjustments to be made in several areas: firstly the oil lines to the
rockers will need to be accommodated, then the rear baffle and the air dams will need to be
adjusted and then the sequence repeated perhaps 2 or 3 times until the fit is correct.
Remove the 2 front and 1 rear rocker cover cap screws (circled top), test fit the duct and mark
the locations for the cutouts around the oil lines (arrowed above). File out a notch for each oil
line until the duct clears them by 1-2mm all round.
Leave the cap screws out and set aside until the final fitting of the ducts is complete.
The front air dams will need to be trimmed to fit around the fins on the cylinder heads and
barrels. The final fit must have the air dams only just touching the fins as shown above.
It may take few trial fits so take your time and get the fit just right.
Right-hand duct
Left-hand duct
Rocker cover
cap screws
Oil lines
Oil line cutouts