1988-85hp Force thumps when I floor it????

[darkalley]

I have a 1988 bayliner bass trophey. when I punch the throttle from a stand still (neutral to full) about half the time I feel a sort of "thump". If I get the boat going slow and then floor it I don't think it makes the sound. The boat runs great and this is my only problem. I think it is the gear slipping but my friend thinks it is the prop slipping. I like to ski behind the boat so going slow isn't always an options. Thanks for your help! Oh and I think the prop is one of those with a rubber bushing in the middle.

 

[DJ]

Re: 1988-85hp Force thumps when I floor it????

darj,<br /><br />Could be either. Here's how to check the prop.<br /><br />1. Make a mark on the prop shaft.<br /><br />2. Make a corresponding mark on the propeller hub (outside of rubber bushing).<br /><br />3. Run the boat and see if the the mark on the prop moved. If so, it's the prop.<br /><br />If not, the gears n the lower unit are slipping.