Shaft bearing replacement questions?

backman

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I'm told my shaft cutlass bearing on a 4 year old/670 hr Northern Bay 36 is delaminating and needs replacing. I'm also told to do so the shaft must come out, and to do that the rudder must also be removed.

Labor quoted is on the order of 20 hrs.

Ignoring the amount of labor quote - must the shaft come out to replace the bearing and must the rudder be dropped to pull the shaft or are there tricks to sneak the bearing out and back in.

I'm familiar with cutlass bearing wear on previous inboards; but what can delaminate? I will be looking with my own eyes this weekend; but here is a picture of "delamination". What else should I be looking for?

shafttube.jpg
 

F/V First Team

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Looks like your rubber is having some issues back there, were you roped up by any chance?

Removing the bearing is fairly easy, just loosen the set screws and take a big pipe wrench and bite into the bronze housing of the bearing, with a twisting motion slide it down the shaft. Have some wooden wedges cut and ready in your back pocket or on the skeg to slide into the open space between your shaft and the tube once the bearing is free. Shaft support is key. Some dawn on the shaft will make the job easier to slide it off and the new one on, just seat your new bearing into the tube and tighten your set screws.
 

backman

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Thank you so much - I knew there was a simpler way!

I can't speak to any rope I have caught up as I only put 100 hours of the 670 on it.

Is that deterioration on the face a MUST fix this winter or can I live with it a year? Will it deteriorate further over time?
 

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well it looks a might bit goofy there, as long as there are some holes for the water to exit the shaft bearing you should be alright. It's not vibrating is it?

They can be quite chewed up and still be just dandy, just doesn't look pretty and should be replaced when it is possible. Mine is a bit mucked up but it's 12 years old and has many, many miles on it. Which leads me to believe that somewhere along the way rope found a home in front of the propeller, and for a while. At least the tube isn't worn down.
 

backman

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I'll look very closely this weekend. I did give it the once over when the boat was hauled and saw no obvious signs of wear.

No vibration on the boat and no asymetrical wear on the bearing.
 

CEShawn

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I also imagine for 20hrs they are doing the one on the inside, if there is one, right?

I've done mine a handful of times, probably no more than every 4 years because I was always told it was a good idea... rethinking that now. I know some are on boats forever but to me that wasnt an excuse. I used to change my aft one in about 1hr because I've done it before. I have to imagine the other side, if there is one can be tough as you would need to move the shaft back, rudder is in the way, etc.

I used to also lube mine back up with soap to get it on easier, not sure this was the best either but worked for years...

Again still trying to learn the better ways...
 

petrel

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I guess those those last a lot longer up north than they do down here boating around these sandy shores in shallow water.
 

tunafishhkg

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I think anytime you can avoid vibration by keeping play down makes for a comfortable quiet ride so replace mine every 3-4yrs depending on how it looks. Sometimes just not using it and being on the hard will dry and crack the cutless. To make it easier next time, have a machinest put a lite thread on the first say half of the outside of new cutless that you can put nut on and screw it out with no chance of damage to the tube face or shaft the next time you change out. He can make you a nut that you can keep since one that big with a shallow thread might be hard to get. If you have trouble finding a machinest, Home Page Can make you one and send it. Lot of utube info on his site about shafting and prop work if you are interested. Good luck
 

captainlarry84

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Looks like your rubber is having some issues back there, were you roped up by any chance?

Removing the bearing is fairly easy, just loosen the set screws and take a big pipe wrench and bite into the bronze housing of the bearing, with a twisting motion slide it down the shaft. Have some wooden wedges cut and ready in your back pocket or on the skeg to slide into the open space between your shaft and the tube once the bearing is free. Shaft support is key. Some dawn on the shaft will make the job easier to slide it off and the new one on, just seat your new bearing into the tube and tighten your set screws.

I concur with 1st Team. You have enough cutlass bearing housing showing to grab & turn it out.
Before you start your pull. I would clean the shaft well with emery to make it nice a smooth, then load it up with Dawn.
You may also want to heat the tube up with a heat gun. Heat always makes things a little easier.
Dropping the rudder is a lot of work and not need as you should be able to pull the bearing.
Down the road if you ever have to pull the shaft we never drop the rudder. We back out the shaft so it touches the rudder the mark center. Next we hole saw drill the rudder. Once done the hole is covered by the rudder zinc.

CCI12182009_00001.jpg

photo 1b.jpg
 

backman

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A couple questions:

First - is it sufficient to support the shaft at the nut end with a stand or blocking as the bearing is twisted out or do I also need support inside the shaft log to avoid damaging the PSS dripless shaft seal?

Second; once out and shimmed with wooden wedges - its now time to slide a new bearing on - any tricks to this past Dawn and carefully juggling the shims an shaft support as the bearing moves up the shaft and into the tube?

Finally - if the twist it out approach goes bad -can my yard potentially damage things?
 

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Anything has the potential to damage something else, that whole "a butterfly flaps its wings in central park and Godzilla destroys Tokyo Tower".

Supporting the nut end isn't a bad idea at all. Sorry to hear about your PSS system, but the cutlass bearing at the other end of your shaft should be more than enough to support that end of things.

Putting the new bearing in place is pretty straight forward, lots of Dawn on the shaft and try to keep the housing of the bearing dry and clean. Makes it easier to grip. A pipe wrench or a chain wrench would make things easier to rotate as you slide it up the shaft, a chain wrench might do less damage to the exterior as well. Just have a few blocks of wood and a hammer, I prefer a deadblow hammer, so you can tap the bearing home when the time comes. With the nut end supported it should be a simple deal to remove the wedges and get everything in place.

It sounds to me that your yard wants to get some work out of you, and unless that quote they gave you includes the interior cutlass bearing I'd pass.
 

Beamie

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I also imagine for 20hrs they are doing the one on the inside, if there is one, right?

So boats of this size and set up have a cutlass on the inside too?

I am just use to changing cutlasses on smaller inboards with one at the end at the wheel and just a flexible 6" rubber hose and stuffing box at the end of the tube on the inside.
 

jwalka51

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I just started doing a new shaft, new cutlass, new pillow block, and new wheel in my 26 webber cove. She had a 1-3/8" shaft and I went up to a 1-1/2 shaft The old shaft was twisted up like a cork screw, the pillow block was installed misaligned, and the engine is about 1/4" low and also misaligned. I got a little ways into removing the rudder and said the hell with this. I unhooked the rudder ram, turned the rudder 90 degrees, pulled the shaft back to the rudder. I traced it, then I broke out the 2" hole saw. It worked great. I own a welding and fabricating shop in newport RI, so naturally my plan was to weld the slug back in when I was done. But then I realized that the hole was super convenient so I decided to put a shaft zinc over it like was previously mentioned so that I could use it in the future. The cutlass was another story. The old one came out easy, and once again the hole in the rudder came in very handy because it gave me a clear path for the slide hammer that I used to bang it out. The new one did not want to go in that easy. I ended up using a 4' piece of 1" threaded rod to pull it in. The cutlass is in, and the shaft. Now I am working on mounting the new pillow block, and then, the task of getting the engine lined up, I cant wait to see some scales stuck to the paint, but until then......... Its a long road to the boat ramp.........
 

Drakes

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They are completely trying to screw you Backman! I would not stand for it! Push that baby back in flush in the tube and spin the prop, then shake it side to side see how much play is actually in it, if there isn't much then dont worry about it, on the other hand if you can wiggle it all around, then change it, and its as simple as one two three to change it, there is only one cutlass bearing that baby I would guess as I have the same boat, its not very far from the engine to the prop so no real reason for a pillow block bearing. If you have a wet stuffing box and if shit was ouit of alignment that would leak more than usual, most likely its fine but for 250 to 300 buckd you can buy a new cutlass and slide it on in like on prom night! ;)
 

Drakes

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Backman,
Did the survey come up with any of these problems you are having? Seems like a lot of stuff going on with that boat...I would sue the surveyor for all these costs you keep having to accrue...
 

jwalka51

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Thats the way that it was when i got it. Would it be ok to get rid of the pillow block and just put another cutlass in the forward end of the shaft tube??? It would be so much easier. Either way, the middle of the shaft needs some kind of support, My engine is all the way up forward,so the shaft is almost 11 feet long. There is only the stern cutlass and the pillow block as of now. I really want to get rid of the block, It seems like it will be nothing but problems. Does anyone have any suggestions???? Any help would be greatly appreciated.
 
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