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Back in 1998 she was repowered with 330's Cummins with 1.5" shafts. I'm attempting to replace the cutlass bearings and it seems the length of the strut and bearing is unconventional. The new cutlass are 6" whereas the strut and old cutlass is 5.5". Do I cut back the new cutlass to 5.5" or do I leave .25" protruding beyond the strut? The old cutlass did not protrude beyond the strut. Can I cut down the length of the cutlass and what would be the recommended way to cut it? Any suggestions are appreciated. 1972 Bertram FB

Don't cut the bearing. Just leave the extra length hanging out of the strut on the side opposite the wheel....bow side.

If you left it on the stern side you reduce space between strut and wheel which can reduce the flow of water thru the bearing...and that is not good.


If you should decide to cut...regular hacksaw will do it in short order. just watch the heat and "No Petroleum" based lubricants should come in contact with Nitril rubber or you risk all sorts of problems...namely the rubber swells and/or turns hard.


I leave' em long all the time.

Wursty,

Don't cut the length, you could end up seperating the rubber from the bronze tube. Just leave it long with the extra length sticking out between the strut and the prop hub...

Thanks Capt Pat & Carl for your suggestions but is it best to have all the extra length of bearing protruding only from the front; or equal on both ends; or only extend toward the back. I think you guys said exactly opposing placement so I asking for clarification. Thank you

Wursty,

If it's truly only a 1/4", it doesn'i much mater what or where... If it's more like 3/4" balance fore to aft.

In truth, you can let bearing hang out the back giving some additional support "if" you have the room, additional support is a good thing.

It is the "if" that makes me say leave the extra length sticking out the other side of the strut.

If prop bearing space is too close, you can impede water flow thru bearing...not good.
If prop bearing space is too close, it makes it a bear to get a prop puller in between prop and strut without pulling shaft down from tranny.

When we machined OEM struts for our customer, prints specified pressing bearings flush to prop end.


But for the most part, we took the "if" out of the equation and it is just our standard to press flush to prop end unless otherwise noted.



We look at the whole group and going flush to prop end of strut is a sure bet for no issues.

Looking at each boat/install individually...one can tweak install and gain a little here and there.