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DiverDan
05-06-2002, 09:33 AM
Well, getting ready to launch, and wondering if I should replace the cutlass bearing this year, or wait until next year. There is a little play in the shaft now, but it was very minor right after haul out. My understanding is that the bearing will dry out over time (7 months out of the water). I am assuming that it will need to be done within a couple years, but last year, when running there was no serious vibrations from the shaft.

Any major tips out there on cutlass replacing? My bearing is in the shaft log from the box garboard keel. Has anyone ever drilled a hole in the rudder to accomodate the shaft to avoid removing the rudder? I have heard that many work boats do this. Any way to remove the bearing without removing the shaft?

Thanks,

dan

Ian McColgin
05-06-2002, 09:55 AM
I have one friend who three times (boy doesn't learn!) removed his perfectly good cutless bearing by having the engin in gear when he did the autum flush-out. Sucked it right up the shaft tube. We actually got new cutless's on without removing the old mess until after that third one, when it seemed like a good idea to start fresh.

Since you need to get the prop off anyway, what exactly is the problem getting the shaft out?

By the way, being a rag and stick sort and a bit casual about these things, I don't change the cutless unless it's really loose.

[ 05-06-2002, 10:56 AM: Message edited by: Ian McColgin ]

DiverDan
05-06-2002, 10:02 AM
Ian, two things I am concerned about and would like to not have to remove the shaft:

1. The shaft coupler to the transmission, I have heard horror stories about trying to get the shaft separated from the coupler

2. To remove the shaft I would have to remove the rudder, which would also mean removing the bottom bracket for the rudder which is held to the keel by several perfectly attached and bedded lags that I would like to keep that way.

thanks, I really don't think it would need to be done this year as it is not "really" loose yet.

d

Ian McColgin
05-06-2002, 11:09 AM
Breaking out at the couple can be a huge pain as there's rarely room to slip the shaft and couple back enough to get a puller in. Sometimes you can back it out a little, put a spacer in on the shaft end such that when you try to refasten the flanges, that will pull the couple off the shaft. You may need to irrigate with penetrating oil, bang on the sides with a hammer, and torch it a bit. Have an extinguisher in your assistant's hands and at the ready!!

Sometimes you'll end up cutting the shaft and buying a new one. Terrible pain.

There are a few boats that won't allow shaft removal without rudder removal, but usually just removing the prop and swinging the rudder hard over does it. Too bad if your boat was designed by a sadist!

G'luck

nedL
05-06-2002, 11:27 AM
Dan, I know what you mean about the 'hole in the rudder' thing - used to see it all the time too. It wouldn't bother me to go that route if it were my boat. (As you say,lots easier than pulling the rudder.)
I too think the worst part of the job might be getting the coupling off the forward end of the shaft.
The only way I could think of to change the cutlass bearing without pulling the shaft would be to remove the whole bronze housing that carries the bearing. Might not be too bad (couple of lag screws into the dead wood), or might be a nightmare ? Either way you will need to get to the forward side of the bearing to either push or pull it out.
If as you say there isn't much play (just a tiny bit) I would probably leave it for now & see how things go. You have one pretty good advantage with your box garboard keel, you are supporting the shaft real solidly nice & close to the prop so you can probably get away with things being a little bit looser.

DiverDan
05-06-2002, 11:33 AM
Ned,

Thought about just taking the prop off and pulling the shaft log out by taking the lags out.

I would have the clearance to do this.

My worry was reseating the lags. Would longer lags be better? Would not want to split anything. Maybe some epoxy in the holes? But then probably never get them out again. Varnish? 3m 5200?

What about alignment problems? If I line up the original holes, should be ok, but if the lags are tightened differently, that would put the alignment off correct??

thanks,

d

nedL
05-06-2002, 02:04 PM
Dan, I don't think you should have to much of an alignment problem if you reseat the log in the same orientation as it came out. You could try a 'test sample' to see how one of the lags unscrews. If things do come apart it would be a good idea to go a bit longer on the new lags, as you said I wouldn't use epoxy or 3m 5200-(just like epoxy) to set the new lags in. The varnish idea sounds pretty good (drill pilot holes for the new length). I'm not really sure how far into the deadwood the log projects. My feeling would be about two inches.

Bob Cleek
05-06-2002, 02:51 PM
While your boat may pose unique problems, if it is anything like every other boat on which I've ever changed a cutless bearing, this is not a hard thing to do at all. (I believe it is a "cut-less" bearing, not a "cutlass" bearing, but no matter.)

First, pull the prop. Ram a big hunk of wood in there between the prop and deadwood to wedge the prop solid so it won't rotate when you remove the prop nut. Back the prop nut off until it is just even with the outside edge of the shaft threading. Take another big block of wood and put it up against the forward edge of the prop right at the shaft. Hit the block of wood smartly with the biggest sledge you can lay hands on. The prop should break free of the shaft. (The nut, which is still on the shaft will keep the prop from flying off the end of the shaft, bouncing on the ground and flying into the drink.) With the prop loose, remove the nut and take off the prop. (Remember to keep an eye on the shaft key. Sometimes they stay put and sometimes they don't You'll need it when the prop goes back on.)

Now remove the two nuts on the hanger bolts which hold the outboard half of the shaft bearing casing onto the boat. This half holds the cutless bearing. Pull the whole thing off... it'll slide off the shaft. Take it to a vise and stick it in there. Remove the set screw that holds the bearing in the housing. (It should have a wire keeper wrapped around the housing and across the screw slot, so cut that off along the way.) The bearing should slide right out of the housing... but they never do... It'll be frozen in there solid. Par for the course. Take a sharp hacksaw and disconnect the blade and run it through the hole in the cutless bearing and reconnect it to the hacksaw. Then, carefully, cut two notches side by side in the edge of the cutless bearing, as far apart as your biggest screwdriver. These notches are cut at a very slight angle into the rubber of the bearing and through the bronze casing of the bearing, but not into the bronze of the bearing housing. Take your screwdriver and bend the bronze edge of the bearing up inside the bearing hole so you get a tab that you can rest your screwdriver against. Then hammer the bearing out of the housing. Install the new bearing in the housing using some good waterproof grease and maybe replacing it next time will be less work. Don't count on that, but it'll make you feel good thinking it will. Put the housing back on the boat with some good bedding compound. Be sure to put the set screw back in the housing. (Sometimes this will require drilling a hole in the outside of the bearing casing for the screw to set into.) Put the prop back on (making sure you grease the shaft well).

As you can see, there's no need to remove the shaft or rudder at all. I hope!

pwilling
05-07-2002, 06:43 PM
Anybody have more thoughts on how to tell when this operation is needed? If you can't get any wobble or play in the shaft by horsing on the prop, leave it alone? Sounds like it could be a good candidate for destructive maintenance.

Mike Keers
05-07-2002, 07:11 PM
I've always been told if you can feel any play by shaking the shaft, it's too much. I know a new shaft and a new cutless don't have any play I can feel. If it's only a bit of play and you don't feel any vibration, it's your call. Be aware you might need a shaft as well, only inspecting the area that runs on the cutless will tell.

Please note in Mr. Cleek's post above his reference to 'hanger bolts'. If you have lags, when you pull the stern bearing off, replace them with hanger bolts for the next time.

You might find you'll have to cut the cutless bearing into several pieces with a hacksaw blade or similar to get it out, even after the set screw(s) is removed. Sometimes they just get corroded in there, even tho' it's all bronze to bronze.