trainfan1 wrote:

I owned/piloted & worked on many jet boats.

I owned/piloted *one* jet boat and its been about 20 years. I *know*
about the flatbottoms, (prop type) I built them for myself and others as
well as raced them but my memory could be playing tricks on me with
regard to how pumps are set up. The idea with a Day Cruiser was to
*avoid* wrenching. I do seem to recall a spline back there and I
know that some way of allowing for slight misalignment is necessary.
What is a Poly isolation coupling? Does it have a spline like a drive
shaft?


I'm looking for the brand Boat or drive/pump - that has u-joints.

You mean you're in the market?