Prop shaft wobble

[Cashew]

Hi,

we have Valiant 40. It is powered by a Yanmar 4JH2E with Paragon and Walter P10S VDrive. The gearbox has been „rebuilt“ by the previous owner, I don’t know any details.

Last year we had a mechanic replace the motor mounts and align the engine. I noticed a wobble in the propshaft which according to the mechanic would be no problem. However, when I read about what play a shaft should have, its mostly said it should be zero and that is not the case for ours.

So here is what we observed:
- There is no bearing in the shaft tube itself, is this the default? The only bearing we have is in the strut, it was replaced last season and I notice no play
- The damper plate springs were worn out and we are replacing the plate
- We have a Maxprop and two anodes on the shaft
- The walter VDrive has no noticeable play when turning by hand
- Sometimes the Maxprop does not fold correctly and the shaft is turned while sailing. I do not notice any wobble in that case
- Wobble occurs in forward and in reverse

I would appreciate any thoughts about how we might find the cause. Unfortunately there is no possibility to haulout around here.

Could misalignment cause this? We thought about a bent shaft, but then it should also wobble when turned by the propeller, shouldn’t it?

I have uploaded a video:
https://youtube.com/shorts/aAoxSHbrN...aq26WrwVuimxSe

The excessive stuffing box dripping is due to wear of the shaft and the stuffing box not filly tightened. We are planning to replace the shaft and seal when we are hauled out next time, however we are unsure how problematic the wobble is.

[deltaten]

Once on the hard, check shaft, at several places, for straight. Use some sort of indicator; could ba a pointed popsicle stick, solidly mounted. Run shift. If gaps anywhere, it's bent
Grab hold of. The shift just aft of the P bracket and rock it in sev er rally directions. Any play? Bearing's(?) Out
Check for engine/shaft alignment