Replacing Cutlass Bearing on Neptunian 33

[pcatterall]

Can anyone offer some advice to my fellowNeptunian owner, Walter, His problem is set out below as is my response.

Many thanks


　


Hi Walter,


Mine has been done following an incident with a lifeboat ( another story1) unfortunately it was done in Southampton and I did not observe the steps.


I will pass this on to the PBO forum where there many very helpful experts Hopefully they will come up with some ideas.

Very good forum to join. Some photos would be useful.



Hi peter happy new year to you hope its a good one.
I hope your getting on better than I am with any boating projects as im a bit stuck and thought you might be able to help.
I am trying to renew the cutlass bearing and wondered if you had done yours.
Not sure if yours is the same but here goes... I have removed prop and shaft and unscrewed the 2 10mm bolts around 1" long that hold a round brass cap which is about 4 " diameter and half inch thick. after a bit of a puzzle I realised that this is also threaded onto the cutlass bearing so I have huffed and puffed and managed to unscrew the end cap. I haven't seen a cutlass bearing that was threaded strange?

Now I can see the bearing and its threaded end is sticking out about a half inch from the stern tube .
I tried to spin or move it with stilsons which damaged the thread but I know its got to come out anyway as its badly worn but it hasn't budged yet. I sprayed with wd40 hoping this will release but I don't hold much hope. Any ideas??

I am also renewing the prop shaft which was marked and pitted by galvanic corrosion and was of thinking of getting one of those shaft bush earth device I was wondering if you had similar trouble in the past.
This boating lark and all its problems seem to whirl around in your head at the worst times and eventually get me out of bed at unearthly hours

 

[Tranona]

I am also renewing the prop shaft which was marked and pitted by galvanic corrosion and was of thinking of getting one of those shaft bush earth device I was wondering if you had similar trouble in the past.

Can't help with the cutlass problem, although a photo might help.

The pitting on the shaft is more likely to be crevice corrosion, quite common on shafts, particularly where the shaft goes through bearings. The shaft brush referred to is not for earthing but is a means of bonding an external anode to the stern gear to prevent galvanic action dezincifying the prop. It won't do anything for the shaft.

It may be that the shaft is not 316 stainless but even if it is there can still be crevice corrosion over time through sitting in static seawater, such as in water lubricated bearings. Make sure the new shaft is 316.

 

[BabaYaga]

Now I can see the bearing and its threaded end is sticking out about a half inch from the stern tube .
I tried to spin or move it with stilsons which damaged the thread but I know its got to come out anyway as its badly worn but it hasn't budged yet. I sprayed with wd40 hoping this will release but I don't hold much hope. Any ideas??

From what I have read there are sometimes grub screws through the "deadwood" holding the bearing in place, so look for those (under layers of antifouling paint). When I changed my bearing some years ago I found no screws, instead the bearing was epoxy glued inside the stern tube. Trying to knock it out from the inside with a big hammer and piece of iron tube was not successful. In the end, I had to use a saw of this type
http://www.toolstop.co.uk/bahco-pc-12-com-procut-compass-saw-300mm-12in-p30934
to make a few cuts lengthwise (easier with a phenolic shell than with a brass one, but likely doable).
Then pry out with a screwdriver or other suitable tool.

 

[vyv_cox]

My Colvic Northerner has what sounds to be the same bearing. After unscrewing the retainer, held in position by two set screws, the bearing is seen underneath. In my case it is a white metal bearing about 4 inches long with around half an inch of larger OD protruding from the stern tube. I used a pipe wrench to remove it, hard work as it was a press fit. It was very worn, so I have replaced it with a Marelon one from Neil_Y of these forums.

White metal is very soft. If it marks easily this will identify it. My bearing is quite thin walled, no space for a conventional rubber bearing.

On mine there is a peg in the stern tube at the inner end of the bearing to prevent it from rotating. I needed to tap it out aftwards for about 1/2 inch before I could rotate it.

 

[NEWDAY]

Thanks peter some good advice from fellow users a great site for information. thanks for all the replies, it looks like I will have to purchase the recommended saw and cut the bearing out. Walter

 

[NEWDAY]

Thanks for the info I did try with a pipe wrench today but it just chewed it up .
I think I need to buy long saw to cut the bearing out. I checked for pegs and removed 2 .

 

[NEWDAY]

Thanks for that.
I also tried a drift from the inside to drive the bearing out but the lip is very small so think I will try the saw

 

[NEWDAY]

Thanks for the advice I think you are correct as mine is water lubricated.