Prop shaft flex

[Risto and Liz]

We hauled today to change zincs and check some things out. I discovered that the shaft has been worn shiny on one side right where it exits the hull. The shaft has a certain amount of flex. I have noticed a kind of vibration at cruising speed that I only hear when on the starboard side deck. I had thought it was something in the Nav station rattling but now wonder if it is the shaft tapping. Maybe it has a slight bend that only shows up at higher revs? I have watched the shaft at the V-drive and it doesn't show any vibration. Any ideas?
http://vid1383.photobucket.com/albums/ah286/SilverWings52/IMG_1179_zpsqwir9nao.mp4

[PeteW]

Definitely a bit of a set back. But you absolutely need to inspect renew every component in that part of the drive train while you have it on the hard. So many things seem wrong in that clip.  Here's what it should look like.



Note how the prop shaft is perfectly centered in the shaft log.

Your shaft looks a little spindly and your v-drive appears to be mounted way off. Shaft needs to be 1 1/8" stainless steel. I assume at this point you're going to pull the shaft to check it for true and replace the cutless bearing (SOP). That will also allow you to also replace the hose and clamps on the stuffing box if they are more than 8-10 years old. You need to check the v-drive output shaft for play with the shaft removed. You can then re-position the V-drive before you go back in. You cannot check the motor alignment until its in the water. Since you are repositioning the v-drive this final step is now required.

At haul out,  misplaced sling will bend the prop shaft. But this problem seems to have been going on for awhile.

Pete

[Della and Dave]

Good luck.  For what it's worth, we just ordered the parts from Oberschreimer  http://obersheimers.com for our stuffing box, just because it was time.  We went with the Buck Algonquin hose, 316 SS T hose clamps and Teflon packing.  We did not go with the graphite packing because of galvanic corrosion concerns.  If you ask Dale, he has the part numbers.  Prices were quite reasonable. 

[Risto and Liz]

We actually had just done a haul and hang to do the zincs. I realized that some of this may be that in May, the diver had added a second zinc to the shaft which he put about 6" aft of the exit from the hull. I replaced that zinc in the same location and realized this morning tha by adding weight to that part of the shaft adds to any shaft whip. Damn I may have to have a diver either remove it or move it aft by the other shaft zinc.
I realize that I will have to replace the cutlass bearing and should change to a SS shaft and new stuffing box, hose, clamps, etc.
I would greatly appreciate any input as to length of shaft, stuffing box part numbers, etc.
This will give me an opportunity to get all the parts before planning a time on the hard.
I will study the alignment info and try to get my head around it before then!

[Risto and Liz]

Interesting... Went for a sail today to remind myself that I really do know how sailboats work! It is all the mechanical stuff where I am on a steep learning curve.
Motoring, I found that the 'knock' was not as pronounced but when I checked the stuffing box, it does, indeed, have quite a bit of movement.
I will plan for a new SS shaft and shaft seal. I am up in the air on the PSS. It sure looks like a good solution, unless it fails ...maybe a drip is better than a river?
While I have everything apart, it seems like a good time to rebuild the V drive. Does anyone have a cost for doing so and a source in Seattle? Are there two v drives? The Walter looks nothing like what we have. Ours looks like the one in the posts tha Pete has made regarding alignment.
Thanks for everyone's advice.

[PeteW]

Risto,
The thing about this site is that  most of the 365's out there leave an indelible history. Your boat is no exception. What's known is that your boat was at some point in time repowered with a larger W40. This probably explains the misalignment.

The other bit of history is that your prop shaft was bent by a misplaced lifting sling. Can't tell if this was ever repaired.  Bronze would not be a good choice.

Anyway, the ease at which your stuffing box is wiping around will also result in a stuffing box  hose that may very well be on its last ply as we speak. I hope you will respect my opinion that uncorrected your boat scores low in seaworthiness.

The failure mechanism is that the hose ruptures under power (at the worst time and place) and the boat sinks. Since its below deck, you don't notice until its coming out of hatches down below. By then its so deep  that you must put your head is underwater in attempt to wrap the hose with anything that will stem the flow of sea water. Its one of my reoccurring nightmares.

Those hoses are  special multi-ply hoses that are very stiff. With my shaft coupler removed from the v-drive I cannot move the shaft by hand but 1/4". You stuffing box hose seems to have lost its structural integrity meaning that its gone beyond end-of-life.

Pete