trailer tongue weight

The correct answer is "as much as it takes". But the school answer is anywhere from 5% of total weight (boat and trailer) to as much as 15%, depends on what school you go to (but 10% usually makes it into any curriculum). However you do it, a multiple axle trailer should be level when hitched ... :?
 
If you get stopped for a roadside check and the scales come out, no more than 10-15%. Depending on your towing vehicle, a LD hitch can make a big difference. We have a 208 on a tandem axle LoadRite and use an '08 SD with factory towing package.
 
the tongue weight on my 204 Overnighter on a double axle trailer is 270 lbs with zero fuel.

I guess that is just a bit over 5% of the total estimated 5000lb combined trailer/boat/motor/batteries/light gear weight. It tows great and I think the 5% tongue weight makes it a little easier on the tow vehicle.
YMMV
 
If you get stopped for a roadside check and the scales come out, no more than 10-15%.

:huh Does that mean a tongue weight of 11% 'might' be overweight, but a weight of 14% might not? A maximum weight 'range' makes no sense. Somewhere in the northeast, right?
 
I haven't actually checked the tongue weight yet, I'm guessing it is somewhere between 180 -200#. The trailer tows ok on the flat but wants to sway when going down hill which gives a real uneasy feeling.