[C320-list] coupler re-install

[Rick Sulewski]

Ted,
You're welcome!
Rick

-----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 10:35 PM
To: C320-List at Catalina320.com
Subject: Re: [C320-list] coupler re-install

Now installed!

Thanks for details.  Worked great. 

Ted 

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
> 
>