[C320-list] coupler re-install

[tharrison at innovations-plus.com]

Thanks Rick. I understand will be giving it a go in an hour.

Sent from my iPhone

> On Apr 25, 2015, at 12:46 PM, "Rick Sulewski" <rsulewski at bex.net> wrote:
> 
> Ted,
> I found that installing the coupler as you suggest works while being certain
> to line up the coupler set screw holes with the shaft dimples and then
> installing the set screws followed by taping in the key. That arrangement
> worked better in my situation when I recently removed the coupler to replace
> an aging 20 year old shaft log hose. I initially attempted to install the
> coupler by installing the key in the shaft and then driving the shaft into
> the coupler when that prop shaft coupler was attached to the engine side
> coupler, using piece of wood to prevent damage to the shaft threads with the
> prop installed, but that approach did not work for my. The boat, while in
> its cradle, naturally experiences a degree of hull flex and the shaft could
> not be driven all of the way into the coupler even with a large degree of
> tapping force at the prop end of the shaft because the shaft did not totally
> line up when it was half way into the coupler. Further movement was being
> held back by a portion of the leading edge of the shaft resisting against
> the coupler due to the degree of  hull flex, creating misalignment while
> resting in the cradle (causing increasing amounts of excessive force
> necessary to continue to drive the shaft into the shaft side coupler which I
> opted not to continue). I then had to remove the partially installed shaft
> from the coupler with the flange puller and reinstall the coupler by driving
> in the key from the engine side after being certain the coupler set screws
> were seated into the dimpled shaft in order to line up the key slots on the
> back side of the shaft & coupler. After tapping in the key more than halfway
> in,  I met with some resistance and then reinstalled the shaft side coupler
> to the engine side coupler and then only had to tap  the end of the prop
> shaft to further drive the key into the last portion of the coupler,
> followed by separating the coupler for additional taps on the key leaving
> the key almost flush with the face of inside edge of the coupler.
> 
> It is important to understand that the coupler should be tightly fit on the
> shaft and the key helps to not only keep the shaft from rotating within the
> coupler, but also serves in my case to fit very snugly between the shaft &
> coupler. If the shaft to coupler fit is too loose, then the shaft could work
> loose (wobble) within the coupler and that could result in the shaft
> separating from the coupler if the shaft side of the set screws shear off
> when operating suddenly in reverse or under strong power in reverse. That is
> why it is not advisable to grease or lubricate the shaft when reinstalling
> the shaft in the coupler because the rust that naturally develops between
> the shaft and coupler serves to also provide a tighter tolerance over time
> between the shaft and coupler. Do not forget to tightly wired the set screws
> to prevent them from working loose.
> 
> As an additional precaution it is advisable to have your prop zinc located
> securely just ahead of your prop strut by a length not greater than exists
> between the coupler and packing log nut in the event the prop shaft may ever
> separate from its coupler with the intent of relying on the shaft zinc to
> (hopefully) keep the shaft from totally exiting/departing beyond the packing
> log nut and creating a large flow of water to overwhelm the bilge pump. 
> 
> Hope this reply is clear. If not, feel free to contact me off line at my
> email address.
> Rick 95 320 hull #277
> 
> -----Original Message-----
> From: C320-list [mailto:c320-list-bounces at lists.catalina320.com] On Behalf
> Of tharrison at innovations-plus.com
> Sent: Saturday, April 25, 2015 10:45 AM
> To: C320-List at Catalina320.com
> Subject: [C320-list] coupler re-install
> 
> Do you put the coupler on the shaft first and then tap the key in with a
> hammer?
> 
> 
> 
> 
> 
> 
> 
> Ted Hull 424
> 
>