Volvo D2-55 / saildrive vibration/cavitation

[Charliemciver]

Hi, about 2000 rpm my saildrive with flex-o-fold prop, driven by d2-55 has developed an odd vibration/cavitation....

I think it started before the prop was cleaned this winter.

The anodes were in good shape so I didn't replace them - I guess I could just to see.

Any suggestions for how to diagnose what the cause is?

[Diesel Bill]

Sounds like a balance problem. Are the blades free? Any nicks or dings on them? Any past impact?

[Charliemciver]

No past impact that I'm aware of. The flex-o-fold prop is now 10 years old. I can see some signs of corrosion after giving it a good clean up this winter. Probably seems a good idea to get the prob rebalanced? In fact I think somewhere I have the original prop which might allow me to eliminate the prop balance as the obvious source of vibration.

[Captsteve53]

Hmmm! 10 years old, I would be looking at the Pins and their corresponding holes through the propeller blade, I have found many quite badly worn causing vibration (funny enough around 2000 rpm) possibly because at those RPM there is less load than higher RP's, my own prop had this issue. we solved it by the machine shop making custom sized pins and retro fitting the assembly, -they didn't open the holes in the housing enough to weaken the assembly , refitted no vibration (or noise in my case)

Cheers Steve

[Charliemciver]

Thanks for the advice - good tips!

[xhogpilot]

I recently found electrolysis pitting on one of my folding props, and when I pulled the hub, I found more significant putting on the face (front of hub facing saildrive. This produced a vibration and required a hub replacement.

This on D2-55C with S130b saildrive

[RuneM]

I had a similar issue with my d1-30 a couple of years ago. Vibrations at 1500 rpm caused by one loose engine mount...

[Charliemciver]

Will check engine mounts Friday and let u know what I find.

[NordicCruiser]

Originally Posted by RuneM

I had a similar issue with my d1-30 a couple of years ago. Vibrations at 1500 rpm caused by one loose engine mount...

@RuneM: Was the engine mount bolt just loose og was the mount faulty in the rubber part and needed to be replaced?

@Charliemciver: Dis the engine mount fix your issue or did you find other conclusions to the vibrations.