Squeaking shaft/drive train

[George Da Porge]

We been out sailing 5 times this season. Have a 2014 ZF transmission. In neutral when sailing. 3rd time out after putting tranny in neutral and shutting engine, heard a continuous regularly varying pitch squeak. Loud enough to be annoying. After nosing around, determined it was coming from prop shaft/drive train. Checked tranny fluid - good. Checked stuffing box - very few drips. Adjusted that so have 7 - 8 drips/minute when shaft is rotating. Have no idea when SB packing was last replaced (we bought boat in spring 2014). No change in squeaking. Squeaking goes away when prop is not turning shaft (shift into gear (rev) when engine off).

Any ideas as to the cause of the squeaking? Thanks!

 

[DaveJ]

Others will comment, but I'm pretty sure you should be sailing with the tranny in reverse, this will stop the rotation of the shaft and take any pressure off the clutch plates. Check your manual. It may say anything but the direction of travel (forward)

Cheers

 

[George Da Porge]

I did confirm with my mechanic that the tranny should be in neutral. Pretty sure manual says same, but will double check. Are you thinking the squeaking is coming from clutch plates? Thanks for the feedback!

 

[DaveJ]

I have a Hurth tranny, which I have been told is the same/similar as the ZF. My manual states to keep it in reverse. I had to do a rebuild this year (525 hours) and the clutch plates were blue from the heat. I always (I think) had it in reverse, but there were 2 previous owners. The noise is either from the packing gland (yours seems OK if it is dripping that much), a bearing (let's hope not) or from contact on the clutch plates. I am no expert, just trying to help, but make sure you follow your manual.

Cheers

 

[kloudie1]

Check the shaft-to-engine coupling alignment.. Check the shaft for straightness.. Sometimes, an alignment problem or a slightly bent shaft will "wiggle" the engine a very little bit when the shaft is turning.. it may be an engine mount or something like the exhaust hose squeaking on fiberglass.. When the engine is running, the noise may be masking the squeak or the motions may be big/fast enough to keep it from squeaking.

 

[JK_Boston_Catalina310]

Check your manual but it likely says in reverse or neutral while sailing. That is what the MX-25PB has. If you want to lock the propeller from spinning but the transmission in reverse. But leaving it in neutral has no negative effects.

MaineSail had posted the studies before on the effect of the propeller on drag. If I recall correctly the MIT study found neutral was the best and I believe MS confirmed this with his own studies.

As for the squeak, try cleaning the prop and shaft. Check for play in your cutlass bearing while you are at it.

 

[George Da Porge]

Thanks for your ideas! Will see about checking alignment (although visually I don't see any obvious misalignment). ZF manual says "zero" position when sailing, engine off, which I assume is neutral. Going to run in reverse, though, until I figure this out. Will have to check the cutlass bearing when we haul out in October. I suppose I could swim under and see if I can wiggle the shaft at the CB. The water's warmed up nicely in southern Green Bay!

 

[hvbaker]

Neutral or reverse is fine.