Mainship 350/390 Cutlass bearing replacement

The friendliest place on the web for anyone who enjoys boating.
If you have answers, please help by responding to the unanswered posts.

HeatherAlyssa

Senior Member
Joined
Mar 11, 2017
Messages
217
Location
United States
Vessel Name
Heather Alyssa
Vessel Make
Mainship 350/390
Hello trawler friends! My propeller is off so I’m going to replace my cutless bearing on my 1999 Mainship 350/390. Single engine 1 3/4 “ shaft. Any tips on the removal of the Cutless bearing would be appreciated. I see two set screws on the starboard side. Do I simply remove those, and then drive some kind of punch from forward to aft on the old bearing? Thank you.

Alex

IMG_1520807330.681590.jpg
 
This is something I feel confident I can do, but I choose to let the yard do it. The hydraulic press and special tools most yards use to remove and replace make the job easy, right tool for the job.
If something goes sideways, a fix might cost extra days on the hard.
If you do choose to DIY, I'm sure there's a you tube video on how to.

Just my $0.02

:socool:
 
Just had my 2000 MS 390 cutlass bearing replaced...it was a challenge for the yard staff. They had all the tools, and still took them almost a day to do. While prop was off, had them strip barnacles and polish the brass like new (also did the rudder as well).
 
Changed loads (hundreds of bearings over many decades in the marine industry. Not something to do lightly, and depends on the installation type. Lots of tricks to learn. However you can get the right tools for your boat (don't need to buy the whole kit) from https://strutpro.com/ They have lots of videos etc. Should give you enough info. Beating bearings out normally frigs the whole installation up and you finish paying the yard to put it right.
 
I talked to the yard. They have the hydraulic kit. They’re going to mic the old bearing and give me the dimensions so I can order one which will be cheaper. Then they’ll freeze the new bearing and swap it out.
 
Then they’ll freeze the new bearing and swap it out.

LOL, reminds of my days riding dirtbikes. I used to do 1-2 sets of wheel bearing replacements per season. Not nearly as complex as a cutlass bearing, but same basic principal. I used to freeze the bearings to ease installation. You should also be able to heat the strut to expand it prior to installation as well. I would be very, very careful not to overheat it. If my wheel hub was too cold, I could hit it with a butane torch for a bit to warm it up and expand it a little. It was the difference between pressing in the bearing and having to beat it into place (which is not ideal, especially on a strut).
 
Got the new bearing. I’ll tell you what I pay for installation when I’m done.

IMG_3058.jpgIMG_3059.jpg
 
Update. $225 for the installation. I bought the bearing myself for $114. I’m pleased.
 
Hi Heather. I have a 99 390 and was wondering what your prop size is, Im looking for a spare, have the single yanmar. K
 
size of Propellr

Hi Heather. I have a 99 390 and was wondering what your prop size is, Im looking for a spare, have the single yanmar. K

I too have a single Caterpillar and would like to know size of Prop if any one knows? or have a picture of one
 
I have a 1997 350 with a single Cat 3116. The boat came with two props a 26 x 24 and a 26 x 26, both 4 blade. The boat hits 2750 rpm with the 26 x 24 and 2675 with the 26 x 26.
 
The Cat 3116 should hit 2800 rpm at WOT. After a have the bottom striped of old bottom paint the 26 x 24 should achieve 2800 rpm.
 

Latest posts

Back
Top Bottom