Replace shaft and cutlass

Dec 25, 2008
1,580
catalina 310 Elk River
So it's been 10yrs on Witz since I redid the drive train (Engine mounts, Cutlass bearing, damper plate, packing). It's time to replace the cutlass bearing and packing again. She gets pulled every year for the winter and runs in fairly silty mostly fresh water, I'm guessing the silt provides enough abrasion to act on the cutlass negatively. I've got the bulk head out now and engine ready to raise to get the shaft out. While sliding the shaft aft for inspection after detaching the coupling from the trany, I noticed that the original bronze shaft had considerable pitting only where the cutlass bearing contacted. This surprised me as being on a mooring and no AC any where near (solar charged). My zinc gets depraved by ~2/3 every year. I will now need to replace the shaft. Catalina direct wants ~$518 for a Aqualoy 17 (basically SS304) + faced coupling. Deep Blue Yachts wants $514 for the same except it is Aqualoy 22 (much better corrosion resistance).
So Why do I want to go with Catalina Direct?
 

paulj

.
Mar 16, 2007
1,361
Catalina 310 Anacortes,Wa
I had the strut bearing replaced and the shaft was OK, but I went with a split flange that was faced with existing shaft ( once only). A split flange eliminates flange removing and replacing problems.
IMG_5385.JPG
IMG_5390.JPG
IMG_5387.JPG
If you have a PSS system, it makes changing the rubber boot every six years a very easy, even with boat in water.

paulj :hook2:
 
Dec 25, 2008
1,580
catalina 310 Elk River
Hey Paul, a split would be nice, but because I use a breakaway adapter a longer flange would probably be a little tight. Not sure how you removed all the cross wiring to provide such great access.
Hope you're doing well.
 

dmax

.
Jul 29, 2018
969
O'Day 35 Buzzards Bay
Buck-Algonqin offers a short version (model # ends with an S) of their split coupling, similar in length to non-split ones.
 

paulj

.
Mar 16, 2007
1,361
Catalina 310 Anacortes,Wa
???? I wouldn't try that. o_O
Well you promise to babysit for one night the kids of the owner of a boat 2 slips down from you in exchange for this, since he is a scuba diver, he stuffs a rag into the the area where the shaft enters the hull to stop the water. Then you replace the boot, then he takes the rag out. Baby sitting at their place was easy peasy..
 
Jun 14, 2010
2,081
Robertson & Caine 2017 Leopard 40 CT
Well you promise to babysit for one night the kids of the owner of a boat 2 slips down from you in exchange for this, since he is a scuba diver, he stuffs a rag into the the area where the shaft enters the hull to stop the water. Then you replace the boot, then he takes the rag out. Baby sitting at their place was easy peasy..
Have you actually tried this?
 

TomY

Alden Forum Moderator
Jun 22, 2004
2,758
Alden 38' Challenger yawl Rockport Harbor
Buck-Algonqin offers a short version (model # ends with an S) of their split coupling, similar in length to non-split ones.
Ayuh. And it sounds like the OP's shaft is simply worn - in cutlass and or stuffing box area - from age. In which case, the simple thing to do is cut it into pieces and measure the remiains, for a new shaft.

You can then install everything new, with ease. I wanted to improve access to the stuffing box for re-stuffing.
Transmission installed.JPG
 
Dec 25, 2008
1,580
catalina 310 Elk River
So I had a discussion about the chemistry with my 99yr old chemical engineer father at dinner last evening (will be 100 in November and still quit with it!) It's clearly not crevicing looks more like a geo topo map. (Pictures to come phone died arrg). He indicated that the vulcanization of rubber involves sulfur which does not play nicely with the copper content in the bronze. So mere prolonged contact has probably caused this.
Will be cutting the sucker out measuring it and going with Agualoy 22, with split coupling. Won't need to borrow that prop puller anymore.
 
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TomY

Alden Forum Moderator
Jun 22, 2004
2,758
Alden 38' Challenger yawl Rockport Harbor
So I had a discussion about the chemistry with my 99yr old chemical engineer father at dinner last evening (will be 100 in November and still quit with it!) It's clearly not crevicing looks more like a geo topo map. (Pictures to come phone died arrg). He indicated that the vulcanization of rubber involves sulfur which does not play nicely with the copper content in the bronze. So mere prolonged contact has probably caused this.
Will be cutting the sucker out measuring it and going with Agualoy 22, with split coupling. Won't need to borrow that prop puller anymore.
In my case, it took less than 2 minutes to cut the shaft. Simple to take the pieces; frozen coupling and shaft stub from below, remaining shaft and prop pulled out of the shaft log, and deliver it to the shop.
IMG_1714.JPG

They took it from there and fit/faced a new split coupling, my prop to the new shaft.

I could have spent a day removing the parts in place (and maybe fail at the end) only to find out the shaft was simply worn in the cutlass area from a few decades of use. But I knew it was worn a bit from the last time I installed a cutlass.

It was a joy to install the new parts, easily.
 
Jul 1, 2010
962
Catalina 350 Lake Huron
. Catalina direct wants ~$518 for a Aqualoy 17 (basically SS304) + faced coupling. Deep Blue Yachts wants $514 for the same except it is Aqualoy 22 (much better corrosion resistance).
So Why do I want to go with Catalina Direct?
I just got a new shaft and coupling for our C350 from Deep Blue Yachts for the very reason you mentioned (I ordered it in A22). They did a nice job with it.
 
Dec 25, 2008
1,580
catalina 310 Elk River
What measurement did Deep Blue reguire? Catalina Direct wants from the start of the taper (do not include threaded portion). Did they provide keys on both ends and castle nut?
 
Dec 25, 2008
1,580
catalina 310 Elk River
Talked to Mike at Deep Blue, he indicated total length and built to SAEJ755.
Depending on how long the threaded portion is would move the prop in or out from it's current position.
My threads extend out from the taper 1 3/8" and the "H" measurement for a 1" shaft is 1 3/4" for SAEJ755, so that would place the prop 3/8" closer to the strut. I will add 3/8" to the total length to keep my gap at 1" from the back of the prop to the strut.
 
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