removing prop shaft...pro job?

[TheMadchef]

Well.
Last season whilst solo sailing in relatively rough seas, i accidentally left a dock line left on deck that went overboard and fouled my propeller. After haulout at the end of the season the boatyard manager informed me that I'd probably need a new cutlass bearing as the line had got wound inside it.
Now as the boat is about to be launched, it is time to deal with this issue. He quoted me $700 - $1500 to do the job of replacing the bearing. My question is can I, as a relatively ignorant mechanic, remove the prop shaft myself and re-install it later to save on labour or is this a job best left to the pros. I have an 18hp volvo diesel in a 29ft sloop.

[weephee]

Would you need to remove the rudder to get the drive shaft (prop shaft) out ? If so, how big a deal is it to remove the rudder. I replaced my cutlass bearing on my 27' Columbia and I had to remove the rudder. If you take it slowly and remember how to put it all back together again, I would think you could do the job if you have any mechanical abilities. Getting the old cutlass bearing out took a bit on ingenuity but everything came together in the end. Check the shaft for wear once it is out. Good luck

[klem]

There is nothing particularly difficult about the job but it can certainly be time consuming. As weephee pointed out, sometime your rudder needs to be removed or sometimes there is even a plug somewhere that needs to be removed to do this. The actual act of removing it once you have done stuff like removing the coupler is usually relatively straight forwards.

If you take your time and think it through, you shouldn't make the situation any worse at least.

[rikhall]

I too think (barring any weird or unforeseen circumstances) that you can do it. I did mine. Removing the cutlass bearing was a piece of cake. Used a hacksaw blade to cut from the inside once the prop shaft was out. Made two cuts opposite each other and it just came apart.

Also - take lots of digital pictures BEFORE each step - make is easier late to answer the question "From which side did that thing go in?"

Rik

[TheMadchef]

thanks guys...i think i will tackle this job with a friend who is an engineer; ofthen these types of jobs are more intimidating than difficult. Ill take lots of pics and let you know how it turns out.

[weephee]

I used an alternative method to cutting the bearing in two places. Once the shaft was removed I replaced it with a 3/4 inch, 4 foot threaded rod. I put a couple of washers the exact size of the od of the cutlass bearing and a nut on the inboard end of the threaded rod and pulled it rearwards until the washer hit up against the inside of the old cutlass bearing. I then slipped a 6 inch long steel sleeve with an ID slightly larger than the OD of the old cutlass bearing over the threaded rod from the rear of the boat (where the prop would be) and then a couple of washers and a nut. Tighten the nut onto the threaded rod until the sleeve hits onto the brass sleeve that the cutlass bearing fits into. As you tighten the nut the old cutlass bearing will slowly be forced outward until it comes out. I put the new cutlass bearing into my house freezer for a while so that it would be a smaller diameter and then with a block of wood, I gently tapped it into the brass sleeve (forget what that sleeve is called but it has a name). I also put a light coating of oil on the outside of the cutlass bearing so it would go in easier. Sounds confusing perhaps but i hope you understand what I'm trying to say.

[weephee]

That brass sleeve is called a stern tube. I need to remember that.

[JimsCAL]

Done it three times. Hardest part dropping the rudder. Dig a hole for this if necessary. Getting the shaft out of the coupling can be tough, especially if this is rusted. Start spraying with PB Blaster ASAP. The cutlass bearing can be removed by slitting it with a hacksaw and then collapsing it. A threaded rod with a couple of large washers or pieces of plate with holes drilled can be used to drive the new bearing in. Don't hammer it it!

[PBzeer]

It's not so much dropping it, as putting it back in. Actually disconnecting and reconnecting are straight forward, checking the alignment once it's back in is generally a time consuming affair.

If you're doing this at a yard, you may be able to rent/borrow an hydraulic press to remove the cutlass bearing, though these don't always do the job.

Also, if there was any tension on the line after it got fouled, if you have a prop shaft, check it visually to make sure it didn't bend (that's what happened to me).

All in all, if you experienced no undue vibrations under power, it should be a fairly straight forward task.

[JimsCAL]

Take a look at Maine's excellent tutorial.

Replacing A Cutlass Bearing Photo Gallery by Compass Marine at pbase.com