Cutlass Bearing Size - Yamaha 25/2

[Ameseys]

It's time to replace my cutlass bearing in my 1979 Yamaha 25. It is a special order and I should have one on hand before haulout. Does anyone have the dimensions for it?

I know it is metric and won't be available locally. It would be great to get suggestions for sourcing one.

Thanks in advance for the help

 

[CalebD]

I think it is going to depend on the diameter of your prop shaft.
I haven't seen metric sizes for Cutless bearings listed.
1 in. = 25 mm
1/2 in. ~= 12 mm

 

[dee.yeah]

Hi Ameseys, may I ask how to identify the bearing should be replaced? My Y25 is also made in 1979.

Thanks!

 

[Boffin]

The bearing is available in the web and it is in imperial unit , internal dia 7/8". I have to check the details which is kept in my boat . Let you know later .

I have replaced it two times in the past 25 years . The price in last year is some US 120.00

 

[Ameseys]

Thanks, so much. It will save me a lot of trouble to order in advance of haul out. Otherwise, my boat will sit in the yard until the part arrives. Please do let me know.

 

[Boffin]

I have some information in hand now. In my Y25, the dimension of the cutlass bearing is , shaft dia. 7/8", outside dia. 1 1/4" (it is an odd size ) , the length is 3.5" to 4".
It is made by Morse Marine bearing . Their model is Blenny , 90-349. You can search in the Google to get the supplier or by others , here is one on sale
http://www.deepblueyachtsupply.com/marine-bearings/naval-brass-inch-cutless-bearings.


There are also some information on site for its replacement



http://www.cruisingworld.com/how-to/maintenance/check-the-cutless-bearing-on-the-hard
http://www.diybob.com/diyCutlessBearing.htm

In the Yamaha , the bearing was fixed by a bolt (set screw)using hexagon key . After you clean the brass strut that supported the bearing/ shaft ,you can see that bolt about 3/8" in dia on one side or both side .
You need some DIY tool to get the bearing out . ( a tube with internal dia of 1 1/4" , a long screw in 3/4" , some wash in 1 1/4". you see the first link for the cutlass bearing replacement and U will understand )

It should be replaced if it has been there for more than 10 years . dee.yeah , that bearing is available in HK .

Good luck.

 

[dee.yeah]

Thx Boffin. Great info on the cutlass bearing. I'll inspect mine on next regular maintenance.

On the other hand, I'm a bit afraid to remove the shaft for cutlass bearing replacement, as re-installing the shaft requires accurate alignment.

 

[Boffin]

For some 25 years , you need to get it replaced. The alignment has been fixed by the position of the bearings , one is the cutlass bearing in the strut outside the hull , the other is a rubber bearing in the bilge . You need to disassemble the coupling from the gear box and from the shaft . You need a set of box wrench , the DIY tool as mentioned before and some works inside and out of course .

 

[dee.yeah]

Boffin, thx again for the reminders. I can imagine how much work it is. I do have the DIY tools which I used to remove the bearings on my motorbike wheel and other work on my bicycles. But I would probably need someone's help if I do it.