Breaking teeth in and of itself shouldn't do more than cause a rattling sound. It is possible, however, that it has jumped a tooth (or more), or (also relatively common on older/long disused engines) that one of the gears the outer (teeth) ring has slipped on the hub, causing massive timing shift. If it ran OK before being laid up and wasn't disturbed during that time, you shouldn't have to rotate the timing cog on the cam. These things don't jump by themselves. I'ld advise you to put that back the way it was, pull the timing cover and see if cam and crank still line up. These are non-interference engines, so no harm will be done if it shifted, and you'll do no harm by realigning them and putting in a new timing gear kit (about $70-$120 depending on quality and supplier). Use OEM style pertinax gears for quietness or 164E/aftermarket metal gears for longevity at the expense of a slightly higher noise level.

Bram