Shaft log bearings ?

Ok , I'm about to order some parts to build a shaft log for a 16' skiff I'm installing a small diesel engine in. I plan on a fixed shaft log from about the center of the boat extending out the transom about a foot to a prop. The prop would be about 75%submerged and would be a sort of surface drive (not a surface drive prop ) with a rudder.
I don't know anything about an inboard boat but I am a heavy equipment mechanic. I intend to use a 2 inch ID tube with bearings and shaft seals on each end. With grease zerks to completely fill up the tube with grease. My question is , should I use sealed bearings or open bearings ? And I just thought , should I use bronze bushings instead ? The boat would spend most of the time on a trailer with day use only.
And , would this arrangement with the prop partially out of the water even work ? The engine is a 9hp Hatz. So it would just be a putt putt . I've seen some videos from Denmark and Sweden with ancient ,wooden boats and motors and it looks so relaxing and simple , I want one !
Any help and suggestions about this arrangement would be appreciated!
Thank you , Mark

 

To start with, the location of the motor is too far forward. All you need is a cutlass bearing at the wet end and a stuffing box by the transmission. Bearings with grease fittings mean that you will make an oil slick in the water which may earn you a ticket.

 

Yeah, the "Sheen Rule" could get you (and yes, it even applies to leaking outboard lowers). Typical modern setup is a gonzo describes, water lubricated cutless bearing just ahead of the prop (to prevent overhang wear), a water filled shaft log, and a gland seal. Also depending on the arrangement and/or transmission, there may also be a thrust bearing and line bearing inboard. If you are talking about a bayou skiff/bateau/pirogue/putt-putt and are going mudding, you will want to install a flushing water system to keep the cutless bearing flushed.

 

@Speeedy6 can you post a photo or two of your 16' skiff please?

I must admit that I am rather dubious about your proposed 'sort of surface drive (not a surface drive prop ) with a rudder.'
Sounds like lots of potential for your propeller to cavitate and not function properly.
Is your hull form a 'typical' sort of flat bottomed skiff shape?
If so, then you might take some inspiration from this very neat 18' skiff design by @Tad (Tad Roberts)
Alder 18' Flat-bottomed Island Support Boat ~ Small Boat Designs by Tad Roberts http://tadroberts.ca/services/small-boats/tender-launch/alder18
She has a very conventional propulsion arrangement with a keel / skeg and a transom hung rudder. Not much at all to go wrong here!
Have a look in particular at this study plan with some details of the propulsion arrangement -
http://tadroberts.ca/services/small-boats/files/images/alder/alder18-study-plan-01.pdf

 

FWIW, for those that are disturbed by "cut-less" and "cutlass"....Its Proper Name is a Cutless Bearing - Here's Why — FollowingSeas https://www.followingseas.media/blog/2017/1/30/name-that-bearing-1

 

Wow , who would-have thought , a water lubricated bearing ? Just from a few comments I can see this won't be so simple as I imagined.
As far as the prop goes, I'll post a pic of it later .
Thank you for the comments. Just the few that have been posted has my brain swimming with thought !

 

Everyone on here loves boats. Loves talking boats. Loves designing boats... I'm about to sound like Forest Gump's friend Bubba. But the engineering and design challenges, combined with the potential "fer messin' about" is the stuff of dreams. I've had advice on here that I could not possibly have afforded to pay for. Because we all love boats.