Stainless steel shaft tube

Hello, has anyone seen this setup before? The stuffing box seems to be fine. Repacked. There is a constant drip where the stainless tube enters the beam/stuffing box (second picture). It appears that sealant has worn down between the tube and the bronze stuffing box. The boatyard naturally wants to pull and cut, but they can’t seem to tell me anything because they “hadn’t seen this before”. Any ideas on fixing the situation would be great. It’s a 31’ sedan Taiwan make, 80hp Lehman. Also, reference on a knowledgable mechanic that knows Taiwan Trawlers in the Anacortes, WA area would be great.

Stainless seems an odd material for a shaft tube. Hope it's well bonded to an anode. If it were me, assuming the boat is out of the water, I would check the cutlass bearing(s), pull the shaft, disassemble the stuffing box from the shaft tube. Then inspect everything, especially the shaft tube for electrolysis.

If everything looks ok, reassemble with proper sealants and maybe new cutlass bearing(s). If there are other issues, it seems foolish to formulate a plan without knowing what the problems are.

Ted

I have the exact same tube and the steel cross member on mine. It was dripping seawater where it entered the fiberglass.

During haul out, I tried taking it apart but it would not budge. I tried removing the stern bearing housing and it would not separate from the hull. 5200 was probably used. Cutting or heating both the tube and housing was the only option to remove the tube. I chose not to do that at this point since the leak was only a constant drip. I ground the sealant with a Dremel around the SS tube where it was protruding from the fiberglass and formed a narrow groove between the tube and fiberglass.

Applied 5200 into the groove and surrounding areas generously. Formed a medium size filet at the junction of the tube and fiberglass. Neatness was not required.

Let it dry for the rest of the haul out, about 10 days.

When the boat was splashed, no leaks around the tube.

That repair was done in 2006. It has not leaked since.

Thanks Syjos. Appreciate the personal experience. I sent you a PM.

The way the tube fits into the fiberglass and the steel channel, I have a feeling that the tube was put in while the glass fibers were being laminated in the mold. I also don't think 5200 was available in 1976 when my boat was built in Taiwan.

Possibly started leaking after everything shrank and settled or with shaft vibration? Speculating.

PO or manufacturer applied 5200 to the inside to stop drip. After 5200 was invented. More speculation.

syjos said:

The way the tube fits into the fiberglass and the steel channel, I have a feeling that the tube was put in while the glass fibers were being laminated in the mold. I also don't think 5200 was available in 1976 when my boat was built in Taiwan.

Possibly started leaking after everything shrank and settled or with shaft vibration? Speculating.

PO or manufacturer applied 5200 to the inside to stop drip. After 5200 was invented. More speculation.

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Interesting. I think I’m going to pull the shaft, check it for trueness, make sure the engine is aligned properly and re-seal the tube with 5200. Terrible timing for me. Our NW summers are short.

Adelaide said:

Interesting. I think I’m going to pull the shaft, check it for trueness, make sure the engine is aligned properly and re-seal the tube with 5200. Terrible timing for me. Our NW summers are short.

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Unless it's more than a slow drip, you could wait till fall to haul out.

I waited a year and a half before hauling out and applying the 5200.

I've seen tt's in Anacortes with rust penetrations in the ss tube that caused leaks. Rust holes were where the tube was covered with concrete in the keel. One boat all the concrete was removed and tube replaced. The other boat they were able to pull the tube by brute force and replace. Neither job looked like fun. ss tube was a dumb idea.

My T.T. had a bad leak around the shaft tube. It had rotted some wood and glass. Everything was true and straight but I was taking on quite a lot of water. Funny thing was, it was fine in the fall and leaked badly upon launch in the spring. My yard cut into the glass until they found solid wood and glass, the cut went back about a foot. They reglassed and supported the tube and it has been fine for a few years now. I have a dripless seal in the shaft but who knows about years ago. Never did really find the "leak point" so I may have the look into the problem at some time in the future but for now it is fine. I have been told that Taiwan Stainless Steel in the 70's was not a great product. I'm sort of waiting for my water tanks to fail. It won't be a huge problem when and if they do fail but I'm not going to do it until it happens.

pete

Update: pulled the boat at Latitude Marine in LaConner. Had the stuffing box pulled apart by Latitude, cleaned the threads let it dry out for a couple days, then twisted it all back together with sealant...... splashed and it all held. Turned out to be not that big of deal. My 1983 SS tube was clean but the sealant had worn through. Feel pretty lucky.

Adelaide said:

Update: pulled the boat at Latitude Marine in LaConner. Had the stuffing box pulled apart by Latitude, cleaned the threads let it dry out for a couple days, then twisted it all back together with sealant...... splashed and it all held. Turned out to be not that big of deal. My 1983 SS tube was clean but the sealant had worn through. Feel pretty lucky.

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I'm curious.

Is the SS tube threaded and screwed into the cutlass bearing housing?

And the stuffing box?

It is into the stuffing box. You physically unbolt the 4 bolts, then twist the whole box off the SS tube. As far as the Cutlass bearing, I’d assume so. Latitude did a real nice job. It’s a shame that they are being forced to close down. That’s another subject.

Adelaide said:

It is into the stuffing box. You physically unbolt the 4 bolts, then twist the whole box off the SS tube. As far as the Cutlass bearing, I’d assume so. Latitude did a real nice job. It’s a shame that they are being forced to close down. That’s another subject.

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What did they do to stop the leaking where the tube goes into the cutlass?

They used pipe sealant on the threads. The old sealant failed after 40 years. The tube is in decent shape and should last for decades longer. It was so obvious what needed to be done that we didn’t bother pulling the shaft. The cutlass bearing was tight and no obvious rubbing in the tube. I’m relieved that it cost me 3 hours worth of work and haul out.