Cutlass Bearing

[zaldog]

I am looking at a boat that needs a new Cutlass Bearing installed exactly how difficult it this to install. If installed at a Boat yard how much? Now to show my ignorance exactly what does it do? It is part of the drive shaft correct?

[sailingdog]

Zaldog-

The cutlass bearing supports the propeller shaft as it exits the boat. It is usually bronze with a rubber sleeve. Through use or engine misalignment, this rubber wears out, and the shaft can wobble as it rotates.

How much it costs depends on the type of boat and the boatyard. It will vary, depending on who is doing the work, time of year, etc.

It isn't all that hard to do if the boat is out of the water and you have a modicum of capabilities with hand tools, and are willing to sweat and bleed for your boat. Here's how to do it roughly... it may vary a bit depending on your boat, but this is the basic idea.


Remove the propeller and shaft. Now, with hacksaw blades, cut through the rubber and bronze of the old bearing. You can't use a proper hacksaw, as the blade has to extend into the middle of the bearing. Make a second cut close to the first, and with pliers (or whatever) remove this little wedge of bearing. What you are trying to do is take a small section of the bearing out so that you can decrease its diameter. This way, you can eventually pry and wriggle the old bearing out.

The bearing is supposed to fit very tightly in the casing. You will have to use a hammer and a block of wood to get it in place.

One trick that can make this a bit easier is to freeze the bearing first. This will make it shrink just a little bit and it may go in easier. With a wood block over the end, drive your new bearing in with vigor.

Remember, friction causes heat, so do this part quickly. You may not get it driven in all the way. If it's less than an inch, just cut the exposed part off with a hacksaw. Now put the shaft and propeller back in.

Be aware that a worn cutlass bearing could indicate improper engine alignment, so re-check this when the work is done.

It is quite possible that your shaft has worn too. Check the propshaft, and if it is scored, then get a new one or you'll end up doing this all over again at the end of the season.

[zaldog]

Thanks for the quick reply, it all makes sense. Spend the money and have someone else sweat, bleed and pound with vigor! :-)

[christyleigh]

Zaldog - As SD mentions - it depends on the boat, but one fairly big issue is -- IF -- you can get the propshaft out without pulling the rudder. I couldn't on my last boat but luckily the 'on the hard' was sand, I dug a hole, pulled my rudder, and completed the task. There are also boatyards with very expensive pullers that will do it with the shaft in. Also I have seen on other lists instructions for making your own puller to extricate the bearing without removing the shaft. A few options - some good, some bad, some expensive $$$$

[Gary M]

Actually you can use the entire hack saw just remove the blade slide it through the bearing and reinstall in the saw frame. And remember if you are doing it to make the cut at the 12 oclock position as this is where the strut is so there is lots of brass there. If you cut into the ring some where else you run the risk of cutting some brass (bronze?) and weakening it.

It is not hard to do if you can get your coupling bolts out, I had to grind mine off, and if the coupling will come off of the shaft. I had to have a special puller made up, and if your rudder is not in the road, I had to remove mine. But other wise it was easy.

Oh yes even though I chilled the bearing I had to heat the strut to get it all the way in. See any one can do it.

[sailingdog]

Gary-

The strut had better be bronze.. or stainless steel. Not all cutlass bearings are in struts... some are in the hull, so the hack saw won't be able to be used the way you describe. It depends on the boat. Some boats, especially those older full-keel designs don't have a prop support strut since the prop exits from the keel into an aperture between the keel and the rudder.

[saurav16]

Anyone use Strut Pro to take off the bearing with out removing the shaft?

For Those Who Like To "DIY"