Cummins 6bta 270hp transmission noise

[Collin]

I’m under contract on a boat with a Cummins 270 hp motor.  I’m unfamiliar with diesel engines and I’m hearing a noise when the boat’s in gear that’s concerning me.   this video is shot with the boat running around 1000 RPM.  The noise is reduced at higher speeds but maybe only because the engine noise overpowers it. You don’t hear the noise in neutral so that’s why I figure it’s the transmission.  It’s a reversing gear transmission. Maybe it’s a completely normal noise that I shouldn’t be alarmed about.   Listen closely, there’s like a clacking sound, it’s either a Clack, click or knock. I can’t describe it well with words.

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[Rob Schepis]

The deck, hatch, insulation, bilge and close coupled reversing gearbox all say Albin 28TE.  Very hard to diagnose sound via a recording.  The last ZF63IV that I heard that sounded like a knocking noise that increased with rpm had a bad bearing and needed to be pulled.  I’d say do your best to get a qualified ZF guy out there.

[Collin]

I made a ton of calls.  It doesn’t seem likely that I’m going to be able to have a mechanic available to look at it.  I’m to remote to get it done.

I watched some videos with sound of us when we were motoring at higher speeds and I do not hear any of that noise.  I remember I going away right after we started to increase speed but there was a lot going on so I might have missed something.

Does anyone have a video with sound of their Cummins going in and out of gear between forward and reverse?

[Collin]

Yea, Albin 28.  What gave it away?

The engine definitely sounded a little different in forward and reverse.  I wasn’t alarmed by that sound because my sailboats transmission was way different sounding in reverse.  <br /><br />

Unfortunately the boat is 2 hours away and it won’t be easy to test it out again before the day I make the final purchase and drive it home.  If that not a normal sound, then I will try to get a mechanic to look at it.

[Rob Schepis]

Albin 28, right?

Is the noise any different in fwd vs rev ?

Try to get down there and listen more carefully if the noise is there at higher rpms or not.

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