worn cutlass bearing

ChrisS

Member III
I just had the bottom cleaned, and the diver noticed that the cutlass bearning is getting pretty worn (the surveyor said it was 30% worn one year ago), and indeed, there seems to be more vibration when motoring.

Aside from the vibration, is there any danger in putting this job off? Will it harm the strut or shaft? I hadn't planned to haul until next year when I was going to do the bottom and a few other things.
 

Glyn Judson

Moderator
Moderator
Cutlass bearing replacement in the water.

Chris, If it's just a matter of not wanting to haul the boat, why not try to find a local with a hydraulic remover? I had mine replaced years ago in the water that way. My dive service has one of these tools and with it, the job was done before I knew it with me high and dry in the cockpit watching all the bubbles in the water. Glyn Judson, E31 hull #55, Marina del Rey, CA
 

Captron

Member III
Cutlass

If the cutlass bearing wears through the rubber part, it can score the shaft to the point of needing a new shaft. Further wear can damage the strut and/or damage the shaft log itself. You don't want to get into replacing either the strut or the shaft log.

If the cutlass bearing is worn to the point where there is considerable shaft play at the strut, you're probably not doing the transmission any good either. If the shaft has enough play, it may be damaging the shaft log or the shaft seal. It's like having the shaft misaligned. The vibration is the shaft flopping around under there.

The cutlass bearing can be pressed out (and the new on back in) without removing the shaft, provided the shaft is clean enough but it is a project usually done with the boat out of the water. While it won't be easy underwater, it can likely be done by an experienced diver/repair man. The pressing tool while not complicated does have several parts that can and do fall out. You sometimes need six hands to get everything lined up and tightened up such that it doesn't need holding anymore. Not a big deal on dry land but a pain in the 'roids under the water.

You'll have to remove the prop, of course, not a big deal on a fixed prop but some folding and feathering types require considerable disassembly and more potential dropped parts. Also note that there are a couple of allen head (usually) set screws holding the cutlass bearing in place. Sometimes these are corroded to the point of needing to be drilled out.

My cutlass bearing would not come out despite having two different pressing tools (not to mention various hammers) The mechanic finally cut it out after removing the shaft. The problem with mine was that the strut is so long (almost 7 inches) that the cutlass bearing was inserted in two pieces. Pressing the forward end of the bearing towards the aft end caused the two parts to bind.

If you have to cut it out, you will need to remove the shaft first, not recommended underwater.

Have fun?
;)
 

jreddington

Member III
Not sure if it was a delay in replacing the cutlass bearing, but had both the bearing and the shaft replaced while I had the engine out last winter. Was planning on just the bearing, but once the bearing was out, found some significant wear on the shaft. Part not bad at $300. Labor wasn't bad either but that's because I was already having the coupling replaced and a dripless shaft seal installed, labor costs I had already bugeted for. A lot less than the $3000 my buddy paid to have his two shafts just trued and aligned on his 42' trawler. (Trying to make myself feel better over the amount of $'s I spent on engine work last winter).

Made my first run of the season yesterday. Runs noticeably smoother now. But not sure how much is due to a new bearing or shaft, or new coupling, engine mounts, and alignment.
 

ChrisS

Member III
Thanks for all the replies here. A diver is going to take a look Friday, see how worn it is, and see if he can do it. I'm leaving for the Sacramento Delta for a week on June 22nd, so I don't want to chance getting stuck in a yard. I am planning on hauling in the spring of '08, and pulling the shaft (which my surveyor said was about 3" too long) to shorten the shaft and install a dripless stuffing box, so I hope to get good news from the diver on Friday. Boat in yard in June=no sailing=no fun.
 
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