[C320-list] Propeller Shaft

[Jon Vez]

In addition to Jeff’s points, you are also putting undue stress on the strut because a heavier prop will indeed induce prop whip.
When I upgraded to an Autoprop on my 320 I also changed out the shaft to SS...

Sent from my iPad

> On Feb 12, 2019, at 5:14 PM, Jeff Hare <Catalina at thehares.com> wrote:
> 
> I guess it's all a matter of degrees.  But here's my take.  Sorry it's long.
> 
> That propeller shaft is probably approaching 22 years of service now.  I'm
> assuming it hasn't been replaced because if it had, it would likely already
> be stainless steel.
> 
> No your prop shaft isn't likely to break off, but hitting a or something or
> wrapping a line while motoring with a heavy prop is a little more likely to
> bend a bronze prop shaft than a Stainless one.
> 
> The bronze prop shaft does have more flex than stainless.  That doesn't
> matter much at all when you have a properly aligned engine/shaft and in
> smooth water.  However under hard load of bumpy seas, you are putting lots
> of uneven loading on the engine and will get more shaft whip.  You should
> see what's happing to your prop shaft in those crazy conditions sometime.
> (probably lose your cookies with your head stuck under the bunk in those
> conditions, but that's another matter.  :) 
> 
> So, in my opinion, if you're changing your prop to a heavier one, you should
> replace your cutlass bearing anyway (unless you just did it) because you
> don't want ANY play to make the shaft whip worse.  Once the cutlass bearing
> is out, there's no better time to do the driveline maintenance.  
> 
> So, upgrade the prop shaft, replace the shaft log, repack the stuffing box
> with GFO (dripless) and pop in a new cutlass bearing and you're all set for
> the next 15 years at least (with normal maintenance of course), right?
> 
> So what does all that cost?  Well, you're already into the prop for $2K at
> least. A new prop shaft, shaft log and cutlass bearing is another ~$400.  At
> this point the labor cost to install those is by far the cheapest it'll ever
> be to do any of this work.  Why not do the job now on *your schedule* and be
> happy with all that work behind you rather than wait until the boat decides
> to have a problem on *It's schedule* right before you head out on vacation
> or already out there?   My boat normally breaks when I'm out there using it,
> not when I'm sitting at the dock (well, except for lightning. Lightning
> broke my boat when it was sitting at the dock...so there's that.) :/
> 
> Cheers!
> -Jeff Hare
> #809
> 
> 
> -----Original Message-----
> From: C320-list <c320-list-bounces at lists.catalina320.com> On Behalf Of Jeff
> Smith
> Sent: Monday, February 11, 2019 6:41 PM
> To: C320-List at Catalina320.com
> Subject: Re: [C320-list] Propeller Shaft
> 
> My C320 came with a Maxprop on a bronze shaft. The previous owner told me he
> thought about converting to SS to reduce the possibility of corrosion. I
> have not heard anyone worry about the shaft breaking from the weight of the
> prop, though.
> 
> I serviced the prop and changed the cutless bearing last fall (thanks
> association for making the tools available) and I did not think paying an
> extra $300 would be worth it to get a SS shaft. You will love the prop,
> though.
> 
> For what it is worth.
> 
> Jeff
> '94, #121
> 
> Get Outlook for iOS<https://aka.ms/o0ukef> ________________________________
> From: C320-list <c320-list-bounces at lists.catalina320.com> on behalf of John
> Anderson <jaanderson627 at hotmail.com>
> Sent: Monday, February 11, 2019 5:39:00 PM
> To: C320-List at Catalina320.com
> Subject: Re: [C320-list] Propeller Shaft
> 
> Roger,
> 
> I have a 2003 Catalina 36 MKII. The previous owner installed a Max Prop on
> the original 1" bronze shaft. I believe the shaft had to be shortened a bit.
> As far as I know, it is still down there.
> 
> Unless your shaft is in bad shape already (which it may be), I don't think
> you'll have any problems with the bronze shaft. Be sure to check the cutless
> bearing and engine alignment.
> 
> The Max Prop works great! You're going to love it!
> 
> Regards,
> John Anderson
> Swellville, Catalina 36 MKII
> Pasadena MD
> 
> -----Original Message-----
> From: C320-list [mailto:c320-list-bounces at lists.catalina320.com] On Behalf
> Of Roger Nitkin
> Sent: Monday, February 11, 2019 3:16 PM
> To: c320-list at catalina320.com
> Subject: [C320-list] Propeller Shaft
> 
> I recently purchased a new Max Prop feathering propeller to replace the
> original 2-blade fixed on my 1997 C-320.
> My mechanic says it's too heavy for the original bronze prop shaft, which
> could snap under the weight and strain and dump my new prop into Davy
> Jones's Locker.
> He suggests I replace the shaft with a new Stainless Steel one.
> Does anyone have any thoughts or experience with this ?
> 
> Roger Nitkin
> Summer Time
> Westport Ct
> 1997 #429
>