on my prostar i every now and then there is a low thump, thud sound when i start to get on the throttle(from a stand still). seems to happen around 5-8 mph. doesnt happen everytime either yesterday only once. i was thinking there was an airlock in the tranny or that something my not be bolted tightly. if anyone has any thoughts id appreciate it.

alan, check the shaft that goes in the tranny collor where it bolts. I had that happen on my 1978 master craft. The key was warn out and I replaced the whole shaft to a new one. Or check and see if the prop is tight.

ok ill check those things. thanks