.comment-link {margin-left:.6em;}

The Cabot 36: Classic Blue Water Sailor

A site to celebrate this great Canadian passage maker.

Monday, March 03, 2008

Cutlass Bearing Replacement - Sizing


I am repowering Meltemi this winter, replacing the Perkins 4-108 with a Beta Marine 28hp 3 cylinder Kubota based engine.

While I am doing this I am taking the opportunity to replace the cutlass bearing. My measurements indicate that the inside diameter of the shaft log is 1 9/16 inches. However, there does not seem to be any available cutlass bearings with this OD, 1 5/8 being the closest.

Is my measurement off? Are the shaft log and cutlass bearing metric? Did there used to be a 1 9/16 OD cutlass bearing size in the the late 1970s? Has anyone replaced their cutlass bearing recently and if so did you have this problem?

Thanks for your help.


Blogger Hope Light said...

Greetings from frozen Georgian Bay,
Its been at least 10 years since I replaced the cutlass bearing on Hope Light #27, (Original Volvo MD3B). I'm sure my focus then was the diameter of the shaft itself as opposed to the inside diameter of the shaft log. Obviously both measurements are an issue. Have you already removed the old bearing? IE Cut it out or pounded it out? I have seen several methods of doing this. Not sure what the most accepted procedure is.
I just dig out the drawings that Ted Brewer did for CabotCraft Industries, dated March 21, 1974. I purchased them from Brewer in the early 80s. They show the "shaft tube' as being 1 1/2" IPS and the propellor shaft as being 1". I'm sure CabotCraft could have varied this but this is the original drawing. These are the only measurements that have any relevance to your question.

4:24 PM  
Blogger scribbler said...

This comment is from Roy Mac Keen, who was at the helm of CCI in the 70s. (KD)

No, we did not use metric bearings. We were basically building for the US market so we tried to avoid metrics.

Your measurements may be correct. I assume that you measured in at least two planes, after cleaning the internal surface with a fine grit paper. . The bearing is pressed into the end of a knurled stainless steel tube. When MELTIMI was built I believe we were leaving about ¾” of the stern tube projecting so that two set screws, at 90 degrees to each other were accessible. The bearing size is correct; 1-5/8 OD x 1” I.D should fit into the tube. If you are having trouble, carefully measure the tube again in a number of places and have a machine shop take an appropriate skim. Also, you could try some heat on the tube from a hair dryer. It may be that you are measuring in cold weather. Let us know how you get along!

Roy Mac Keen

Bahamas Marine International Inc

10731 Buttonwood Lake Rd

Boca Raton, Fl 33498-1654

Mobile 954 520 4558


5:53 PM  

Post a Comment

<< Home