Replacing cutlass bearing with prop shaft in situ?

Tim Good

Tim Good

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Has anyone used anything like this to change a cutlass bearing without removing the shaft?

strutpro.jpg


 
The Seastream has a long keel with the cutless bearing housed internally in the shaft log/tube. The tools you show are only
of use for removing a cutless bearing held externally in a P bracket where you have access to both sides of the prop shaft.
When you find a way of easily removing an internally held cutless bearing without taking the shaft out please let me know as I want to replace mine!
 
Yes but I think that is exactly what he has! I would never take the cutlass out of a P bracket without one, shaft in or out! I recently witnessed a renowned East Coast engineer removing a cutlass from a P bracket with ten minutes vigorous use of a drift and lump hammer, I hate to think what he did to the integrity of the bracket fixing. I am lucky in having an extractor as shown in the vid made by a engineering nurd mate but it shouldn't cost to much to get one made.
 
I assumed as the OP has a pic of a Seastream beside his name and a tag that shows he belongs to the Seastream owners assoc, that he would have such a vessel. Perhaps some were built with P brackets? Unlikely but one never knows what lies beneath the water.
 
Hadenough said:
I recently witnessed a renowned East Coast engineer removing a cutlass from a P bracket with ten minutes vigorous use of a drift and lump hammer, I hate to think what he did to the integrity of the bracket fixing. I am lucky in having an extractor as shown in the vid made by a engineering nurd mate but it shouldn't cost to much to get one made.
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And the potential for damage to gearbox bearings
 
Sinbad1951 said:
Perhaps some were built with P brackets? Unlikely but one never knows what lies beneath the water.
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Yes indeed they were. In fact all the Seastreams, 34's and 43s (including mine) I have seen out of the water, have P brackets.

Should I expect my engineer to have such a cutlass bearing tool? Is it relatively commonplace? I think he is planning to hammer it out with some implement.
 
northcave said:
Should I expect my engineer to have such a cutlass bearing tool? Is it relatively commonplace? I think he is planning to hammer it out with some implement.
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Absolutely he should have cutlass bearing tool. I would tell him in writing that you do not want a hammer used at all and ask to see the tool he intends to use.
 
TQA said:
Absolutely he should have cutlass bearing tool. I would tell him in writing that you do not want a hammer used at all and ask to see the tool he intends to use.
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+1. Some P-brackets are quite lightly attached to the hull, but even if not there is a long lever arm that will impose heavy shock loads on the fitting. It is bad practice to hammer anything on a boat. A few light taps OK, but prolonged hammering to remove a bearing would be frowned upon by any decent engineer.
 
Norman_E said:
I made an extraction tool of somewhat lighter construction than the ones pictured. Mine was made from 10mm aluminium plate with 10mm stainless studding and a split tube machined from a short piece of scaffolding. Photo of some of the parts: http://i35.photobucket.com/albums/d164/Sauniere59/tn_CutlassBearingTool007.jpg
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$46 for a frame photo of you cutlass bearing tool! Bargain.

Is that designed for a specific shaft size or will it work on various? Would you like to rent it to me and make some money back for the time it took you to manufacture?
 
vyv_cox said:
+1. Some P-brackets are quite lightly attached to the hull, but even if not there is a long lever arm that will impose heavy shock loads on the fitting. It is bad practice to hammer anything on a boat. A few light taps OK, but prolonged hammering to remove a bearing would be frowned upon by any decent engineer.
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There's also the issue of how much gap you have between the P bracket and the shaft at the forward 'blind' end. Having had a nose around the yard a while ago and some have virtually none which means that the 'pushing' part of the tool would have to be very thin.
 
northcave said:
$46 for a frame photo of you cutlass bearing tool! Bargain.

Is that designed for a specific shaft size or will it work on various? Would you like to rent it to me and make some money back for the time it took you to manufacture?
Click to expand...

Sorry, but I'm not responsible for Photobucket's attempts to get money out people! :)

Mine was made for a 30mm shaft, and would work on shafts of 35mm. Its in Turkey, on the boat so a bit difficult to lend. Its was very easy to make. You don't have to finish it off as nicely as I did. The studding, nut and washers are just standard hardware and the two plates could be quite crudely made and still work. The split tube just needs you to find a piece of steel pipe with a bigger internal diameter than your shaft and an external diameter a bit smaller than the outside diameter of the bearing. Cut the ends square and saw it lengthwise with a hacksaw. In use it helps to hinge the two parts of the tube together with a piece of gaffer tape so that they stay in place on the shaft whilst you assemble the rest of the kit.
 
Also made my own extractor for a few pounds. Not heavy duty but have used it twice so far. I had some steel plate lying around and bought a couple of lengths of scrap tubing in 2 sizes plus some threaded bar. Really Heath Robinson but works well.

I cut the plate into 2 squares and cut a U shape in 1 to fit over the shaft and other goes sits at the prop. end. Holes in the plate to take threaded bar, plus a small oblong piece of plate to act as a gate at the open end of plate with the U shaped hole. That makes up 2 plates, one over the shaft and other at tapered end for prop. These are pulled together by tightening nuts on the threaded bar (3 lengths).

I cut a piece of tube in half along the length and these are just clamped on the shaft with cable ties. The wider piece of tubing just sits over the other end of the P bracket and is wide enough for the bearing to slip through and narrow enough to just sit on the bracket.


Sorry if the description isn't very clear but am in a bit of a hurry just now. The bracket is in Spain at the moment but I might be able to find some pictures to help with my terrible explanation above.

Main point of the post is that you can make one for a few pounds if you visit a scrapyard (not car type) and have a drill, hacksaw etc. plus some time. I'd be surprised to find a "marine" engineer who hadn't bought a decent one or just made one from bits (much better than mine) as it is an easy enough job.
 
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Out of interest... assuming I do get the bearing out and assuming this gives me enough room to get my prop shaft out on one side of my skeg.... does a new cutlass bearing need to be installed with the prop out or can they be installed with the prop in situ also?
 
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