Strange clunking noise in stern drive??!!

[tanyon9864]

I have a 1973 Fiberform 18' skiboat, and I just recently put a new head on it, to replace a cracked one. I took it out to the lake to run it, and once I started getting to a faster speed, it started making a strange clucking noise out the back like something was slipping, it wouldn't do it when I was going slow, only when I was going fast?! any advice would be greatly appreciated!!!

 

[Bondo]

Re: Strange clunking noise in stern drive??!!

Ya Gotta Tell Us What Sterndrive You've Got....????.....<br /><br />Look for Filings in the Lower Unit Oil.....

 

[Liquid_force]

Re: Strange clunking noise in stern drive??!!

sounds a lot like what my drive was doing right before the lwr unit gears/clutch went out.<br /><br />If you're lucky a transom shift cable replacement and/or adjustment may help.

 

[Trent]

Re: Strange clunking noise in stern drive??!!

Cracked head... And now its slipping? Sounds like a bad coupler? But as was said... Need to know what kind of outdrive you have. A bad coupler will cause it to overheat.