Inboard Vibration and Cutlass Bearing

mightyhye

Recruit
Joined
Oct 6, 2008
Messages
5
getting some vibration at over 2000 rpm and I just ordered a cutlass bearing (cause the boat was ran in gear dry! a big no no) for my 1993 Sanger direct drive with the 5.7ltr mercruiser competition ski motor. Been doing alot of research on replacing the bearing and shaft packing and was wondering if I need to remove the shaft to replace the cutlass bearing?

Hypothetically couldn't I just remove the prop then the shaft strut and press out the old and in the new then re-attach the strut? What type of alignment issues would I face with the strut if I removed it?

And overall is it a better idea to leave the strut in place, remove the prop and shaft and change the cutlass bearing with the strut still in place on the boat? then just align the shaft after re-installation?

just trying to make this as easy as possible as i've heard removing the prop shaft can be a @#!@%.

thxs,

shawn
 

cr2k

Captain
Joined
Mar 19, 2009
Messages
3,730
Re: Inboard Vibration and Cutlass Bearing

If you are lucky you can get away with leaving both the support and the shaft in place. undo the set screws and with a long small punch you may be able to drive the bushing out (towards the prop). if not I would remove the prop and then the support. a little silicone on the shaft should make the bushing slide easier.
 

mightyhye

Recruit
Joined
Oct 6, 2008
Messages
5
Re: Inboard Vibration and Cutlass Bearing

thxs cr2k-

unfortunately there are two cutlass bearings in the shaft. (its about a 7" long strut) and they split one 6" bearing and put one towards each end of the strut and left a gap in between each bearing in the middle of the strut.

taking both out and putting two new ones in the same fashion with the shaft and strut still in place would be near impossible. I'll probably remove the prop and strut like you suggested so that I can avoid the difficult shaft removal issues.

anybody else see a problem with removing the shaft strut and replacing the cutlass bearings with the strut off the boat? More or less difficult to align the strut or the shaft?

thxs,

shawn
 

picklenjim

Chief Petty Officer
Joined
Mar 11, 2009
Messages
528
Re: Inboard Vibration and Cutlass Bearing

I don't know how you could do it without removing the strut.Unless there is some type of press that allows you to do it on the boat.That bearing fits extremely tight in the strut and needs to be pressed in with the right tools.You can't just drive them in with a punch.If your not careful you can easily damage the new bearing.If you are thinking of changing the packing you will need to remove the shaft anyway.You could leave the shaft on though and just remove the prop and strut.The shafts are easy to remove.Just disconnect the flange on the end and loosen the packing nut and slide it out.Be sure the shaft is smooth where it runs in the cutlass bearing.Also be sure it's not bent.Roll it on flat concrete to check for bends.If it has a vibration in it it's probably more than a cutlass bearing.You can have them straightened or go to a marina that handles big cruisers and they usually make them there.Just draw a line around the strut on the bottom of the boat with a sharpie so you can put it back on in the same place.
 
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