Changing shaft log o

I am in the process of changing the Shaft log on my thirty four marine trader Has anybody ever done This job. Was wondering how they got it done.

There are a bunch of different types of shaft logs. Can you post some photos of your shaft log? We can give more informed advice if we know exactly which one you have.

It is buried in the keel not gonna get a picture of it.

How will you work on it? Are you changing the whole shaft logor just replacing the packing?

The whole shift log.

Ok, then you will need to know the shaft diameter and the diameter of the stern tube in order to buy the log. Then it is pretty easy if you can get to it. Uncouple the transmission from the prop shaft and remove the coupler from the shaft. Loosen the shaft log at the forward and rear ends. Slide the prop shaft to the stern enough to get the old shaft log off the shaft. Then break the old log loose from the stern tube and slide it off the front of the prop shaft. Then do the reverse to install the new one. After it is done I would check the engine alignment. I may have left out some minor details but this is the general process.

Oops sorry about that I mean the Stern tube we have to change the Stern tube large project. Just wondering if anybody else has done it?

Yes, that is a huge job. Fortunately I have never had to do that on any of my boats.

Dom61 said:

Oops sorry about that I mean the Stern tube we have to change the Stern tube large project. Just wondering if anybody else has done it?

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No, I decided not to do it as I researched for about 6 months and called at least a dozen yards known to do it who all recommended don't bother.

Some of the jobs went easy and most were very difficult.

A few have posted here that they did it, one showing major cutouts of the hull alongside the shaft log and major jackhammering the concrete fuller out of the keel from the inside of the boat.

Some have experimented with liners and coating the old one with an epoxy filler/surface. Never say any good results over the long term....not that they were failures, just not enough data.

Problem is are you the do it or sync it's leaking that bad?

I completely ground off the bottom of my boat, replaced a 6 foot by 4 foot by 1/2 inch deep section of bad glass, ground through a crack at the bottom of the keel and opened up a 3 foot long hole to let the water out and dry (then repared)....and finally covered the bottom with glass cloth and Interlux Interprotect 2000......pretty much rebuilt the entire boat from keel up (all by myself)

In my Avatar I list my old boat as an Albin 40/PSN. The new owner nickednamed it just a PSN 40 since he knows how different she is from a factory one.

I still thought the work versus gain for fixing the shaft log just wasn't worth it.

Why do you feel the need to? Just because it may be leaking into the keel?

What is leaking and why do you want to replace? I am curious because I have the same boat and am contemplating this project, but it is not a priority yet and I am not sure I want to.

It's leaking into the bildge really bad like sinking bad

We were sinking

You should be able to seal the bilge from the keel cavity...can you detect where the water is coming in?

Yes but 1975 mt34 has a false floor

If you can find where it is coming you may be able to seal with toilet wax ring to prevent sinking.

I had a little water seeping in where my water lift muffler was mounted.

It took two gulch pumps running continuously and one every now and then to keep us afloat when this happened it's really bad

I had to do some bilge floor repair when we bought ours. The bilge floor directly under the forward hatch had broken fiberglass and the concrete was exposed. I can understand how a really bad tube could flood the boat. I talked to another person that had the exact same experience you did including near sinking.

It was close but we had 4 bildge pumps running pumped it. All out got under control and got towboat to give us a tow . We weren't sure what was wrong so I didn't want to take a chance on driving

Dom61 said:

Yes but 1975 mt34 has a false floor

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So did mine.....I just sealed it.

Dom,

I did that on the green boat. Had to cut out the false floor and dig out water logged foam. The stink of the foam was terrible.

Photo 1 shows the log after cutting out the false floor. The tabbing has been cut and everything ready to come out.

Photo 2 is the old log with the leak circled in red.

I bought the tube from Nor" Easter Yachts in Milford, CT.

https://noreasteryachts.com/


Rob

It’s major work and costly butI sleep much better knowing I’m not relying on my bilge pumps and batteries to keep my boat off the bottom of the slip. Much like Datenight, cut false floor, removed shaft tube, installed new tube with cutlass bearing in middle (yes GB 32’s were built with this center tube bearing), new cutlass bearings front and stern with new shaft log. Filled void under false floor, reglassed and while we are here and spending a ton go ahead with new SS shaft. But on the plus side I was doing a wind and current aided 9 knots with all the work from Rockport to Seabrook last month, don’t know what I’m going to do with all that extra time.

I forgot to mention ours was also leaking where it went through the hull. After cutting the tabbing it would have fallen out if not horizontal.

Rob

Willard 36 Hull #1 (1961) had this done in 1995 or so. I believe it was a bronze tube about 6-feet long (fiberglass would be better), mostly encased in concrete. I do not know why it needed replacement but it did. Was about $10k at the time in San Francisco Bay. So figure $20k-$25k in today's dollars. Its hard work, but much is simple grunt work (at least until the new tube needs to be installed and aligned).

The OP's posts are pretty cryptic. Sounds serious - not a lot of choice about doing this given the alternative. Longshot, but if this were caused by a grounding, perhaps there is an insurance claim possible?

Best of luck ----

Peter

Stern tube

Dom61 said:

Oops sorry about that I mean the Stern tube we have to change the Stern tube large project. Just wondering if anybody else has done it?

Click to expand...

We removed both shafts (twin diesels) and easily pryed our stern tubes off.
It had old stuffing boxes and during repacking realized after a better inspection that the stern tube needed rebeding. Just like every thru hull.
The mistake we made in rebeding port side with 5200 ( maybe a mistake on this side) is it wasnt completely straight with the shaft.
We converted to pss dripless shaft seals and the port side will now spray water do to be uncentered with shaft.
I suppose after time the carbon ring will work its self to proper seating but I don't want all that spray in the engine compartment.
Next project will be trying to remove the 5200 and rebed.

Dom61 said:

Oops sorry about that I mean the Stern tube we have to change the Stern tube large project. Just wondering if anybody else has done it?

Click to expand...

I did it last year on my Californian 55. Six cutlass bearings and a stern tube. Took over a week in the yard just for that job although I was there longer to get much more done.

JosieWhales said:

We removed both shafts (twin diesels) and easily pryed our stern tubes off.
It had old stuffing boxes and during repacking realized after a better inspection that the stern tube needed rebeding. Just like every thru hull.
The mistake we made in rebeding port side with 5200 ( maybe a mistake on this side) is it wasnt completely straight with the shaft.
We converted to pss dripless shaft seals and the port side will now spray water do to be uncentered with shaft.
I suppose after time the carbon ring will work its self to proper seating but I don't want all that spray in the engine compartment.
Next project will be trying to remove the 5200 and rebed.

Click to expand...

It could be an optical illusion but it looks like the stern tube is not axially aligned with the shaft and therefore the bellows are not concentric on each end. PSS seals do not like that. The graphite seal needs to float on the shaft and not rub on it. It looks like it may be rubbing which will cause spraying if there is any vibration. I've found I need to be very careful with the position of the bellows on the stern tube or it sprays. Once it's aligns if you spin the shaft you should be able to move the graphite seal all the way around towards the shaft and have some movement.

lwarden said:

It could be an optical illusion but it looks like the stern tube is not axially aligned with the shaft and therefore the bellows are not concentric on each end. PSS seals do not like that. The graphite seal needs to float on the shaft and not rub on it. It looks like it may be rubbing which will cause spraying if there is any vibration. I've found I need to be very careful with the position of the bellows on the stern tube or it sprays. Once it's aligns if you spin the shaft you should be able to move the graphite seal all the way around towards the shaft and have some movement.

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I agree. I thought it looks out of alignment but I thought it was just me. I think it will wear badly over time.

I've not ever done it but in theory, it could be done without so much destruction.

Find a hole saw the same OD (or slightly less) than the existing tube. Machine a mandrel that is slightly smaller in diameter than the ID, that fastens to the tooth side of the hole saw to guide it. Fabricate a LONG extension for a serious drill motor. Feed it through until the old tube is gone. I'm not minimizing the amount of work involved, or the number of hole saw blades you will go through, but it should work. Bonus points would be to make the extension drive hollow and feed water through it: cools the saw and flushes the detritus out. Or you may be able to just run water in the other end. This is something like how a gun drill works. Then bond a new tube in. That's what I'd try.