[C320-list] AtoProp Feedback

[resloat]

Brian-I echo Andrew previous post.

I installed an AutoProp on Hull 894 (2002) in 2004.  I used a shaft spacer 
ordered from Spurs in Fort Lauderdale , FL.  I is solid steel.  I checked to 
see if you can get those soft couplers and none come in a thickness as small 
as I needed.  You need to give them a lot of info on your shaft and coupling 
size and design.  The key was to add enough space to prevent the blade from 
touching the strut when they flip from forward to reverse.  I don't think 
this is a problem as you stop the blade when in neutral before shifting 
gears and any contact is glancing.  The folks at AB Marine who are the US 
distributor told me to get a shaft spacer. Mine was 5/8' thick, but you need 
to do some figuring to see what spacer thickness is needed for the swinging 
blade (from forward to reverse position) to clear the strut and still keep 
the length from the back of the strut to the front of the prop less than the 
recommended 1.5" to keep the shaft from deflecting and inducing additional 
vibration. Make sure you add 1/16" to the shaft spacer thickness you design 
because when you install the prop the prop nut on tightening will move the 
prop forward ever so slightly.

Also, Spurs will sell you longer bolts with nuts in the correct diameter. 
You might want to do some searching to figure out how to redo the safety 
wiring on the coupler nuts in the aircraft mechanic mode as the originals on 
mine were.  I reused the safety wire installed by the factory.

I also installed the Gortex packing in the shaft packing gland and have 
basically a dripless system for about $16 and a little labor.  It was the 
best bang for the marine buck ever spent.  My owners manual gives the 
packing spec as 3/16" but measured mine at 1/4" using common drills as a 
gauge.  Only two wraps of the Gortex would fit on the initial install and 
the next season I added the third wrap.

Bob Sloat
----- Original Message ----- 
From: "Brian Borchers" <slaintec320 at gmail.com>
To: <C320-List at Catalina320.com>
Sent: Thursday, May 16, 2013 4:36 AM
Subject: [C320-list] AtoProp Feedback



Hello,

I am considering an Autoprop for our 320. I reviewed some photos  of 
"Nauti - Duck" on the C320 web site and it looked like the strut had a cut 
out, does anyone know if this was done to accommodate the propeller?   Those 
who have the Autoprop or have had an Autoprop, your feedback and experience 
regarding the propeller is appreciated.

Brian