think prop hit something; bent shaft?

[Jared1048]

about a week ago I heart a loud "thump" while motoring and turned off motor to check things out and everything seamed fine.

Now I've noticed that the engine is having to work harder to get to the same speed and is putting out noticably more black soot at 2800 rpm.

it could be my imagination but it also feels like it's just plain running rougher while looking at prop shaft spinning. Its got a little wobble by maybe 3/16ths of an inch.

I think it could be a timing issue and just needs to be tuned up? Engine has 1050 hours and bought it a year ago with 750. I haven't had the injectors looked at but am doing it soon.

What to do?

Thanks,
Jared

 

[Rick486]

Have you checked for warp around the shaft? If not, from experience, you may have a bent prop blade or two.

 

[Jared1048]

How to check for warp on shaft?

 

[Dan Johnson]

Jared...

You're gonna have to get wet to do it!

While you're down there, see if all the prop blades are angled the same way or if one or more are bent...

 

[Jared1048]

Had diesel mechanic come out and found the problem. A friend changed the speedometer from mph to knots and I forgot about it! So instead of doing 8.6 we were doing 7.? And freaked out. Guess that's better than something serious! Doh!