Carbon build up on propeller shaft

[stakultexsun]

2025 bayliner vr5 with about 55 hours on it.
4.5 liter 200hp mercruiser with alpha one stem drive.

I've been trying different props to pull me up on a slalom ski. Finally got that going well after 4th prop.

This is a 15" 15 pitch 3 blade EMP propeller. Boat goes 39.5 to 40mph at around 4740rpms, pulls me up on a slalom pretty good after I ihad dealer nstall SE300 hydrofoil.

Anyway, I do notice some vibration at around 2krpms.

I'm guessing the carbon build up is from the exhaust, but I'm also wondering about this prop. I plan to buy a better one now that I know this works... but I'm wondering if this prop is defective or whatever... it's new and paint is peeling off.

See photos and tell me what you think.

 

[stakultexsun]

Also, just had the 100 hour service, they checked engine for codes or faults, none found

 

[cyclops222]

You need a better marina. Did you show them that soot on your finger ? If yes. They are useless as trouble shooters. Look for a better place.

 

[Pmt133]

Vibration around 2k seems normal for a V6. I wouldn't worry about that.

The soot is interesting. I don't know that I ever cleaned inside my hub out but I do know I've never gotten any soot off it... could be normal for EFI. I assume this has catalyst?