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Its alway something with the damn boat. At the end of last season the motor that runs the head burnt up. Of course the head and the motor are no longer made. I was fortunate to find the same motor, from a removed head, in one of the faithful's junk drawers.Over the winter the new motor arrived and my B-I-L took it apart, cleaned and lubed it for me. So today I wired it up, ran fine. Then I went to re-install it and the SOB won't turn the shaft that runs a recirculating squirrel cage that is the heart of the system. Take a look at my sketch. (Looks like The Far Side Doesn't It? )




The shaft comes up throu a hole and into a "bowl" both of which are in a fixed position, the motor is affixed from above. The two shafts are connected via a plastic coupler that accepts the opposing slotted shaft ends. All shaft ends are intact, all coupler slots are unstripped, both ends of the coupler fit on both shafts. But when I flip the switch the engine whines and the tell tale sound of sewage churning is not heard. For whatever reason the coupler is no longer long enough to bridge the gap. I fooled around w/ it for 1/2 hour without getting "contact".

Not really wanting to comission a machine shop to fab a coupler, I dreamed up the replacement coupler shown in the lower right hand corner of my sketch. Round steel bar is cut to length and slots are cut to accomodate the shafts. I drill out a hole to accept a pin that will hold the coupler plumb on the motor shaft. I really don't have any way to do so with the other shaft. I'm thinking I can do this work w/ my dremel and a small cobalt drill bit.

What do you think? More importantly what do you suggest?

So your going to all this trouble so that when the replacement motor takes a crap(pun intended), you can search again for another?

Time to replace it.

Tear out an operable head over an inch long part? She got her bottom blasted, filled and barrier coated this year along with new rudders. Maybe next year... (I generaly wizz in a coffee can anyway)

Found these parts at the local hardware store. Close but not quite. A slotted nylon bolt inside a tapped nylon sleeve will yield an easily adjustable and replaceable coupler. I bet someone around here has bins full of nylon "hardware", I just have to find them.



The old piece:

I just bought a whole new bottom section . Motor new and other stuff. just reused the bowl but I had a Raritan. Kept the old bowl but all new bottom. That will save you quite a bit. New bottom section is around $300.00 at WMJ Marine. Happy commoding! Dave K

Get a machinist to reproduce it in aluminum.

I would think that the nylon coupling was meant to shear if things bound up. I had a similar situation with a sewer treatment unit where the coupling between the motor and air pump was bad. I drilled holes in the side of a steel sleeve near each end and tapped the holes for set screws. I slid each shaft half way into the sleeve and drilled dimples in both shafts at the set screw holes. Tightened the set screws and it worked. Not sure from your sketch if you have access to the coupler during assembly, but if you do, this might work. No more shear affect though.

Eddy G.