Help with Propeller Shaft and Strut Install

[elucil]

I'm reinstalling my repaired propeller shaft strut. The boat is new to me and the strut was bent and broken when I started this project. I'm wondering about the correct order for reinstalling the propeller shaft and strut. I have reinstalled the strut and pushed the propeller shaft through the log, but it's not lining up with the marks I placed on the propeller collar and the engine before sending off everything for repair.

My big question do I attach the prop shaft collar to the transmission on the engine first and then re-bed the propeller shaft to get it all lined up?

Any help would be great. Thx. Pictures for reference.

[MicHughV]

It is 100% important that those two flanges line up.....to within a few thou of an inch.
At the same time, the shaft should be...correction...must be 100% centered in the shaft log.
Assuming that the shaft is in it's correct location, loosen the engine mounts, and move the engine sideways and up/down as needed until those two flanges mate perfectly.
You can gauge this be inserting a feeler gauge between the two flanges..on a coupler that size about a 0.003" inch gap is acceptable.

Don't rush this process, it takes time, keep rotating the feeler gauge around the flange to determine which way to move the engine.

[elucil]

So even though all this lined up before I have to move the engine to fit the shaft and not rebed the prop shaft strut to line up with the engine?

[MicHughV]

I'm not there so can't tell, but if the original shaft was bent and broken, it was likely due to a misalignment issue.
It would be worth your while to get someone familiar with a marine diesel/shaft installation to either do it for you, or guide you through the process.

The above photograph clearly illustrates that the two flanges don't line up, signaling a problem somewhere.

It could be the shaft alignment is off, or the engine alignment is off, or both.

It must be done right, otherwise you will have all sorts of issue later.

It's not a process that can be hurried.

I see a rubber hose at the end of the shaft tube, this means the weight of the shaft and coupler is enough to deflect that hose, so that the shaft is not centered in that tube. So that is the first thing that needs to be addressed. You have to ensure that the shaft is properly centered in that tube AND also the strut out back. This will require you make and install a cradle to support the shaft, after removing the rubber hose so you can see what you are doing.
Once you've have ensured the shaft is correctly and centrally aligned, you can reasonable assume the flange coupler will be in the correct place and you will likely have to move the engine to bring the engine flange against the prop flange with only 0.003" gap.

If it sounds complicated, it is, because it is.
Which is why I recommend you have a professional assist you in the matter.

[elucil]

I've renovated a number of boats, but first re-bedding of a strut. I feel fairly confident I can handle it, just looking for help to piece all the steps and you have given me some great insight.

It appears the dry fit needs to be precise before anything and I have learned the dripless needs to be off the log and using a "wooden V" to support the propeller is key and that's a great help. Anything else you can recommend would be welcome.

[MicHughV]

I don't see where you have a dripless stuffing box...looks like a conventional stuffing box to me.
Yes, it needs to come off, but leave it attached to the hose, remove the hose from the shaft log and push it forward so you can see the shaft. Then block up the shaft so it is central in the shaft log. I make this out of wood, with shims, so I can move it incrementally. You can also leave the shaft flange on, if you want as it gives a nice visual as to where you are in relation to the engine flange.
But, you should also check the strut on the back, the shaft needs to be central in this too. A complicated process requiring the removal of the shaft, and running a string thru the rear shaft bearing and the shaft log and measuring the clearance.
Alternately, once you've aligned the shaft tube, you can rotate the shaft by hand and feel if it binds on the rear strut. It shouldn't bind, but rotate smoothly. That bearing is water lubricated, you can splash some water in there to facilitate the turning of the shaft.

Kinda hard to explain this by written method, but hopefully, you get my drift.