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Wayne Tassin asked about CS Props.

When fitting the prop to the engine make sure the flange sits cleanly in
the crankshaft 'O' ring to ensure a good oil-tight seal.  The CS pump is
usually spring loaded and sits on the fine pitch stop.  This means that you
will need to connect the lever/push-pull control to it in the fully forward
position and make sure that there is sufficient cable to allow the pump's
lever arm full movement.

Fitting and making the cut-outs in the spinner needs some care.

1)  The drawing for the spinner cutouts given in the 320 Builder's Manual
is highly inaccurate so do not use it!  To fit the spinner past the prop
blades proceed as follows.

     a. Use a cardboard template cut to pass over the blades in the fully
fine postion (ie as shipped).
     b. Clamp two pieces of 2x1" boards about 5' long to one of the prop
blades (protect the blade from damage!).  Using this as a lever you will
be able to move the blades through their full range of movement (ie
fine to coarse)
     c. Moving the blades will allow the cardboard template to be
re-shaped to take in to account the movement of the blades.  You need to
leave about 1/4" of room around the cut-outs.
     d. Transfer the template to the spinner and cut out.
     e. Position spinner on prop and backplate with a pencil just touching
the spinner about 1" aft of the tip.  A camera tripod is useful for
holding the pencil against the spinner.
     f. Rotate the prop & spinner until the pencil describes a perfect
circle on the spinner.  This will mean that, when finally fixed, the
spinner will not "wobble" when the engine is running.  When you are
happy that the spinner is centred start drilling locating holes to
attach the spinner to the backplate.  Check the centralisation of
the spinner regularly whilst you do this.
     g. When basic locating holes have bee drilled and the spinner is
clecoed on to your satisfaction you can remove the whole lot and fit the
anchor nuts to the backplate etc.
     h. The manual recommends that the cut-outs from the spinner be used
to fill the resultant gap formed aft of each blade.  I found this
difficult because the cutout is best removed a little small and then
the edges filed away to fit precisely.  This means that the left-over
material is not useful for filling the aft side of the cutout.  My
solution was to make the filling pieces from aluminium.  The aluminium
cutouts had a 1/4" flange pressed into them to which are riveted anchor
nuts the same size as those used on the backplate.  This method adds
strength to the fit of the spinner to the backplate by carrying the
metal fixings deep in to the spinner itself (ie forward of the actual
blades).

Finally, if you have any conflict between the baffling, alternator and
steel pipe which connects the CSU pump to the forward part of the engine
(typical on rear mounted CSU's)  Lycoming has an alternative, flexible
hose for the job.  I do not know the part number but it is STC'd for the
320/360 engines.

Regards,

Michael


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