cutlass bearing replacement 31

[orientalnc2010]

I replaced my cutlass bearing and was very surprised that the retaining bolts were not only stainless steel but were also drilled through and tapped into the bronze body of the cutlass. Seems like an invitation to electrolysis. I am ready to replace them with silicon bronze and would like to just run them in hard ( but not enough to deform) against the cutlass with no drilling. There are allen head set screws made for this kind of job. They have a concave end to bite into metal when tightened but they are stainless steel. Does anyone know of a source for this type of set screw made of silicon bronze, thread size 10/24.
Any ideas about my concerns are welcome.

[stevemac00]

You have gone further than I ever have but in the interest of educating me and the rest of the PSc collective I'll ask if strength of SS 316 v. silicon bronze is a factor.

As for a source I've found Bolt Depot - Nuts and Bolts, Screws and Fasteners online has a good selection. There's also McMaster-Carr - both I've used with high satisfaction although I didn't check if they had you specific request.

[orientalnc2010]

Hi Steve,
I did buy some new silicon bronze hardware from the bolt depot, they are local for me. Thanks for the suggestion of Mc Master Carr, they do carry monel set screws that should work fine. There have the concave end that should dig nicely into the cutlass and keep her from spinning.
Monel has a value of .30v on the anodic index, bronze has a value of .45v, the differencce of .15v should be acceptable.
Does anyone else have any comments about the compatability?

[orientalnc2010]

As promised I am reporting back with my cutlass situation. The reason the cutlass wore out so quickly is that the shaft alignment in the cutlass was off.
I did the following,
realigned engine so the shaft was centered in the shaft log
dropped the rudder
pulled the shaft and sent it out to the machine shop
had prop checked at same time
cut one side of the cutlass and removed it
installed new cutlass
used set screws to hold cutlass, did not drill and tap as factory install
while installing shaft I slid on new PSS shaft seal
aligned the coupling and the transmission flange to .005 tolerance
painted prop with Petit zinc shield, it was removed to check shaft
applied bottom paint to surfaces to be hidden by rudder
installed rudder
The centering of the shaft in the shaft log along with aligning the coupling flange with the transmission flange within .005 was the toughest part of the job. I will realign the flange and coupling after I launch and rig the boat for the season.
The shaft moves smoothly and easily with no binding at any point while turning it by hand at the prop. When the coupling alignment is out more that .005 you can actually feel the shaft bind as you rotate the prop through 360 degrees.
All is now good

[T37Chef]

I'm going through a similar experience, and the alignment was likely the culprit. I am replacing the engine mounts and glad I am, after removing two of them you can easily tell how worn out they were. You may consider adding a shaft clamp/collar after the PSS for some "insurance".

[orientalnc2010]

Hi T37,
Good recommendation about the extra insurance with an extra collar on the shaft. A doughnut zinc placed behind the rotor should do the trick.
What engine go you have? I had a westerbeke in my previous boat and at certain RPM's anything loose down below would rattle. The yanmar in my PSC is much smoother, I would not have thought that the engine was out of alignment,
only when my conventional stuffing box would not stay cool did I investigate.
Did you pull your shaft and have it checked for straightness? Also have the shop face your coupling to the shaft. This too is good insurance that alignment will be correct.

[npsoa2002]

I replaced the cutless bearing on our Dana a couple of years ago by using standard schedule 40 black pipe from Ace hardware. The ID is just a few thousands over 1" and the OD is 1.315" which is just under the the shaft liner tube. With all the foreign material now days I would varify the deminsions before using the pipe.
I removed the coupling from the shaft that attaches to the transmission, removed the stuffing box and hose from the stuffing box to the stern tube and slid a 4" long piece of pipe over the shaft maybe two at this point and then slid an 1-1/8" box wrench (fits a 3/4 bolt head) over the shaft and started hitting it with a hammer to drive out the bearing. I also put a board between the prop shaft and the rudder so as to not possibly damage the rudder in any way.
Once you move the shaft a little you can grab it with channel locks or a pipe wrench and twist it on out.
When I installed the new cutless bearing I left about a 1/4" stick out so I could twist it out the next time and not remove the coupling.

J LeCocq
Dana Lynn Marie

[bjung]

I replaced the cutlass bearing on our PSC 31 yesterday, and am surprised how fast the job went. There is about an inch of bearing protruding from the shaft log. I first sprayed penetrant into the setscrew holes and let it sit a while, then I used a pair of vice grips on the bearing and started rotating it. More penetrant and more rotating for about 1/2 hour, until it moved smoothly. Then I cut a notch big enough to receive a large screwdriver into the bearing. After a little prying against a metal shim to protect the skeg, it started coming out. More shims, and a couple more notches later, it was out.
The whole process, including removing prop, cutter, zincs and bearing and reassembly only took about 2 hours and 3 beers.
The shaft aligned perfectly, which was an added bonus (reason for beer #4).
Having said that, it will propably take me about 2 days next time.
Bernd
PSC 31 #83

[lsbrodsky]

There is not always that much bearing exposed but Deaton's did that for me to make it easier the next time. Good job!
Larry

[bjung]

Originally Posted by lsbrodsky

There is not always that much bearing exposed but Deaton's did that for me to make it easier the next time. Good job!
Larry

Thanks for you foresight, Larry!
Bernd