What size cutlass bearing do I have?

[mikentosh]

Is there any way to know what size cutlass bearing I have by knowing the boat information and engine info? Or do I have to take it off and measure it first?

I have: 1973 Gulfstar MarkII 36ft.

Thanks for any help.
Mike

 

[Comodave]

Most likely you will have to haul the boat and measure it. You can measure it before you remove it because during removal you may destroy it. Maybe not but it is good to have the correct one on hand before you start removing the old one.

 

[Ski in NC]

Measure shaft size in the boat. There are usually two or three OD sizes for that shaft size. Check with your fave vendor and see that they have all in stock. Once you get the boat on the hill and measure OD, order what you need and you will have it soon enough to not slow you down.

 

[Arc]

You get the first measurement from the shaft diameter. Length can be cut to fit. Outside diameter is a ?

 

[mikentosh]

I was hoping someone on this forum has the same boat and knows the size. Sounds like I have to haul it out and measure it and hope I find it locally or I am paying for hard time while it ships.

 

[Ski in NC]

Jump in the water with a cheap caliper and measure bearing OD at the front of the strut. Not easy to do with good accuracy, but should get you close enough to order new.

 

[sbman]

I was hoping someone on this forum has the same boat and knows the size. Sounds like I have to haul it out and measure it and hope I find it locally or I am paying for hard time while it ships.

Even if you find the original measurement, you never know if things might have changed over the years as things were maintained and repaired. The shaft size can be measured in the engine room just aft of the transmission coupler. You could hire a diver to measure the O.D. in the water and then order the bearing ahead of time.

 

[jgwinks]

Jump in the water with a cheap caliper and measure bearing OD at the front of the strut. Not easy to do with good accuracy, but should get you close enough to order new.

And the different OD's available for a particular ID are pretty obvious. Example for 1 1/2" shaft it can be 2" OD or 2 3/8". Huge difference, easy to tell even in poor visibility.
If your'e buying locally you could just get both sizes and return the wrong one later. They're about $100 each so make sure they'll take it back.

 

[jgwinks]

Length can be an issue too. For 1 1/2" shaft the bearings come 6" long, and most struts are the same. Saw on one of the forums, might have been a sailboat forum, the poster's strut took a bearing considerably longer than standard for that diameter. Only option was to buy two bearings and cut them to fit the longer strut.
I'm replacing the bearings on my boat. Twin 1 1/2" shafts with two struts each. Main struts take 6" long bearings which is standard. Intermediate bearings are only 2 3/4" long so I'll cut one bearing in half to do both struts.

 

[Ski in NC]

Bearing length not a big deal. Many struts are longer than popular bearings, that does not mean bearing has to match that length. Can be shorter, but whole system has to be reviewed to make that call.

If you need one shorter, just about every yard has a bandsaw. The cut easily.