Vibration under power

[Steve]

I knew my cutlass bearing was bad so when I pulled the boat to do the bottom I planned on having it replaced. The yard showed me that my prop shaft was slightly bent just aft of the strut...so I replaced the shaft as well. They sent the prop in to be reworked. Now back in the water and my vibration problem is worse! They just finished aligning the shaft and now are telling me that my prop must be replaced. I suspect that they used the new prop shaft as a pry bar when removing the cap (where the emergency tiller handle fits) at the top of the rudder shaft (rudder had to be removed to install new prop shaft). Any ideas? If I do go ahead and order a new prop they are suggesting I get a 3-blade instead of the 2-blade? My Catalina 36 has a 21hp Universal diesel with 2:1 transmission. Appreciate any thoughts.

 

[Rodd C.]

If you go 3 blade...

Buy a Michigan sailor prop. The size you need is a 15" Dia X 9 Pitch X 1 Inch shaft right hand rotation. I just bought one from New Englan Propeller for about 380.00. Try checking your motor mounts as well something seems fishy with a new cutlass, shaft and repaired prop and still vibrating.

 

[John Visser]

cutlass bearing size

My C-36 is a 1984 model. Can you tell me the size/part number for the bearing?Thanks,jv

 

[Stanley J. Rogacevicz]

Cutless Bearing

John, This is a paste in from a c36 owner, so unless they changed the shaft or strut size in different years this should be the bearing for you.Boatfix.com it is $28 compared to West Marine at $60 the size is calledblackfish 1"x1 1/4"x4". This also fits my c320 and I have recently installed one.Stan"Christy Leigh"c320 #656

 

[John Visser]

Thanks!

I appreciate it. How did you change it, pull the shaft, or use a special tool?jv

 

[Stanley J. Rogacevicz]

Cutless Bearing II

John, I dropped the rudder (had to) and pulled the shaft. I have heard the tool exists for cutless removal - shaft in, but it's a big buck marina tool. I have also heard about homemade tools to do same, but since I am on a sand lot I took the easy and safe way of digging a hole and dropping the rudder. With the shaft removed simply detach and then re-attach a hacksaw blade now inside the bearing, saw through it and remove after loosening the allen set screws. Heat the strut with a butane torch to expand, take the bearing that has been put on ice to shrink, lubed with soap, and with a rubber mallet and wood block it can be easily/carefully pounded in without fear of bearing or strut damage.Stan"Christy Leigh"c320 #656

 

[Steve]

Cutlass bearing size

John, I will try to find out. The yard replaced it for me. Should know by Monday.

 

[Matt Blender]

Before you haul the boat, you might have someone else (other than the people who put in the bearing and shaft) check the shaft alignment and motor mounts.