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On Sun, 11 Apr 2010 18:52:39 -0400, "mmc" wrote:


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. ..
On Sun, 11 Apr 2010 12:02:30 -0400, "mmc" wrote:

A pontoon still has a step where the hulls level out a bit higher in
the water than pure displacement. More speed generally raises that up
a little but at a pretty good increase in fuel consumption.
If the motor and boat are well matched it will be up on the step and
leveled out at 3200 - 3400 RPM. Bumping that up to around 4000 RPM
gives you a good cruise speed and a healthy RPM for a 2 stroke engine.
.
I'm just happy to keep my prop deep enough in the water to keep the
cavitation down. When cruising around the Banana or Indian Rivers, any
chop
at all will cause it to cavitate at 3,000-3,800 RPMs and if almost can't
run
at over 4k at all.
It's a long shaft 50 Force and the cavitation plate is just under the
surface. Should I move the motor lower? Probably involve a either one of
those brackets used to move an OB out from the transome (name escapes me
this morning) or chopping the crap out of my outboard mount, something
I'd
really like to avoid.

That sounds high. The cavitation plate should be below water going at
any speed. If it is barely underwater at rest it will be lifting out.
Where is it in relation to the skid on the motor bracket?That was what
I used as a guide on mine. It sits about an inch below the bottom of a
straight edge, laid on the skid plate.

Sorry about the bad resolution, it is the only picture I could find
http://gfretwell.com/ftp/engine%20mounting.jpg

I can see it fine. Also, I can see where the prop is in relation to the
pontoons.
Thanks and I'll compare it to mine. Or compare mine to yours. Boats that
is.
Ha!


Bear in mind this is 4" above the stock location and the prop does
blow out on a hard turn at speed. My goal was shallow running
Thanks, I'm just trying to run down what my problem is and this will help I
think. How deep was your cav plate in the stock position? We're shallow in
the IR Lagoon too but I still have a good couple feet whereever I want to
go.