Two things

If it is handy and you can get a mechanic to take the boat out with you
and see how it operates, thats better than in the shop with the lower
end rinning in a tub.

If the dealer says it's "ok" then take it out and run the tar out of it
till something deffinately goes out.

Record it all, and if the dealer gives you any flack, thats what they
make claims courts for.