Ethan,
I have had this issue along with some others while I was sorting out my tilt...yes, Most likely you have broken the little pin that connects the shaft to the worm gear. If memory serves here (and it may not) I believe that if you have the tilt motor off you should be able to pull that shaft out without any further disassembly, however if you did break the little pin, you will want to get in to the clutch assembly and worm gear to make sure you don't have any "shrapnel" in there.
I ordered a replacement worm gear shaft online that came with a pin... here is a link for the pin itself (6 bucks) the same site has gaskets and seals for the rest of the tilt assembly as well..
http://www.go2marine.com/product.do?no=100570Fgood luck,
B.C.
Received on Friday, 19 June 2009