Tides dripless bearing frozen to shaft

[Reefgeorge]

I have a Tides Marine dripless bearing assembly that is frozen to the shaft. Apparently, there is only a few thousandths clearance between the shaft OD and the ID of the body of the seal assembly body that can get cemented together from marine growth or mineral deposits (or "swelling" as suggested elsewhere). The housing now rotates with the shaft instead of remaining stationary and holding the lip seal in place. The rubber bellows/hose ("articulating hose") is intact and not leaking. I understand the brute force method of fixing this by cutting the housing off, pulling the shaft back/coupling off and replacing the entire assembly but is there a way of freeing this assembly up while still in the water and saving the current installation? Can that space be opened up mechanically (like raking out a brick joint) or chemically or water pressure?

It would be great to save what I have but as a bare minimum I need to make the boat moveable to get to a yard.

 

[Boatsb]

If it's the type with the front accessible lip seal pull the seal and see if there is growth there or is the seal stuck on the shaft. I don't thing the housing is only a few thousands larger than the shaft. It's more than that to allow water to flow back out for cooling.

 

[Reefgeorge]

It is the type where the front retainer is removed and then the lip seal is pulled out towards the transmission. I would not have thought that the fit between the shaft and housing is that tight but Tides told me that its only about ten thousands all the way around and about 4 inches back. Apparently that interface is a bearing of sorts itself. They did not give me instructions on how to free this up only that its a tight fit and try something like a feeler gauge. I was hoping to find someone who has dealt with this before so that I can go down to the boat this weekend armed with the right "tools". The only thing that I found elsewhere on the internet are descriptions of this same problem where the assembly rips the cooling hoses off and spins everything around like a weed wacker or wraps the hoses around the shaft in a rats nest. I had both. Unfortunately nobody has offered an in water fix.

 

[Boatsb]

A few is less than 10 thousanths. Even though, I though it was a bit more than that. Pull the face seal and see what you have. I thing you may be able to break it free with the seal out. Then again I like the old fashioned ones. Less problems.

 

[Reefgeorge]

A few thousands is indeed less then ten but the issue is still in trying to find what type of material can be that thin, penetrate up to 4", conform to the curvature of the shaft, cut through the crud and not mangle the shaft or housing. When I take a .010" feeler gauge and imagine using something like that to accomplish the above, it seems like a challenge.

After I get through this issue, I may in fact go back to a conventional shaft seal.

 

[Dan Mapes]

This is all why I start the engines and bump them in and out of gear at the dock once in a while.

 

[bobk]

The 'glue' is probably either salts which will dissolve in a weak acid, or a chitin like material like clam shells. Acid might also attack this, but may need to be stronger. You might also try DMSO (dimethyl sulfoxide) but be forewarned, DO NOT get it on your skin. It has the ability to carry all sorts of contaminants into the body. Either way, tincture of time will be needed. Penetrating 4" will be slow.

Let us know how you solve it.

Bobk

 

[Reefgeorge]

This is all why I start the engines and bump them in and out of gear at the dock once in a while.

I had been doing that which suggests that for this bearing system running on a more frequent basis may be necessary.

 

[Reefgeorge]

The 'glue' is probably either salts which will dissolve in a weak acid, or a chitin like material like clam shells. Acid might also attack this, but may need to be stronger. You might also try DMSO (dimethyl sulfoxide) but be forewarned, DO NOT get it on your skin. It has the ability to carry all sorts of contaminants into the body. Either way, tincture of time will be needed. Penetrating 4" will be slow.

Let us know how you solve it.

Bobk

What acid do you suggest?

 

[bobk]

What acid do you suggest?

I'd start with vinegar or lemon juice (citric acid) and see if it froths up. If so it's working. You can go up in increments if you wish. Oxalic plus lemon juice would be next. This does a great job on waterline tannic stains. Last and strongest would be phosphoric. Muriatic is too volatile and will cause corrosion in the ER.

Bobk

 

[Reefgeorge]

It turns out the the general spacing between the shaft and the body that holds the lip seal is very small. The thinnest material that I had with me today is 0.009" and it won't go in. The Tides website brags about how this thin spacing prevents a lot of water from coming into the boat during a seal change. I am not so sure that it is a plus. I would rather deal with a lot of water coming in every 5 years when I change the seal and not have this problem. I pulled out the lip seal and the assembly was still frozen. I tapped around it with a hammer and then tapped the face until it moved towards the shaft log maybe .020". Now I can turn the shaft. The assembly comes with the shaft for a few degrees then stops as the rubber hose starts twisting. All of this did start some water flowing into the boat. There are small thin channels that run the length of the assembly along the shaft line and I got some 0.010 shim material to go about half way through one of them. I need something stiffer so I will try some thicker material tomorrow. Acid won't work because a thin stream of water is coming in around sections of the shaft and will just wash it away.

If anyone has every had to deal with this and has any ideas, I sure would like to hear them.

Thanks.

 

[Reefgeorge]

I'd start with vinegar or lemon juice (citric acid) and see if it froths up. If so it's working. You can go up in increments if you wish. Oxalic plus lemon juice would be next. This does a great job on waterline tannic stains. Last and strongest would be phosphoric. Muriatic is too volatile and will cause corrosion in the ER.

Bobk

Thinking about this some more, I am thinking about leaving the lip seal in and injecting some acid into one of the cooling water hoses and letting the assembly cook in the acid and salt water. What are your thoughts on any problems that I might have with the shaft stainless with these various acids?

 

[bobk]

Thinking about this some more, I am thinking about leaving the lip seal in and injecting some acid into one of the cooling water hoses and letting the assembly cook in the acid and salt water. What are your thoughts on any problems that I might have with the shaft stainless with these various acids?

Somehow I thought you were out of water when I made the acid suggestion. I think you will be OK. Do you know if any cooling water is going through the hose now? You will have to provide some pressure to get it to flow. What we don't know is what other materials are in there. Perhaps the manufacturer can advise.

That said, maybe you can pump some vinegar into the hose and wiggle the shaft back and forth and help the acid get between the water channels quickly. That's what I would try first if I were to attempt it.

Bobk

 

[dsharp]

Mild acid won't have an adverse reaction to the stainless shaft. What is the seal retainer made of? Acid and aluminum don't go together well.

 

[Reefgeorge]

Somehow I thought you were out of water when I made the acid suggestion. I think you will be OK. Do you know if any cooling water is going through the hose now? You will have to provide some pressure to get it to flow. What we don't know is what other materials are in there. Perhaps the manufacturer can advise.

That said, maybe you can pump some vinegar into the hose and wiggle the shaft back and forth and help the acid get between the water channels quickly. That's what I would try first if I were to attempt it.

Bobk

When the lip seal is back in there is now some water flow out of the cooling water injection hose barbs. That is the plan to inject acid under pressure and rock the shaft back and forth. I am contacting the manufacturer today to find out about acid compatibility. Do you know if any of the acids we discussed wil damage the stainless shaft?

Thanks

 

[Reefgeorge]

Mild acid won't have an adverse reaction to the stainless shaft. What is the seal retainer made of? Acid and aluminum don't go together well.

The lip seal is solid rubber and maybe plastic. When you say mild do you mean diluted or that acetic, citric, oxalic and phosporic are mild by nature?

There is a little material buit up on the shaft where the lip seal came out. I tried to chip some off for a reaction test but it just turns to dust and the water coming in washes it away. It looks like the shark skin that you get onthe props/shaft under the boat which I guess is mineral so acid should work if it can get to the offending areas.

 

[bobk]

The lip seal is solid rubber and maybe plastic. When you say mild do you mean diluted or that acetic, citric, oxalic and phosporic are mild by nature?

There is a little material buit up on the shaft where the lip seal came out. I tried to chip some off for a reaction test but it just turns to dust and the water coming in washes it away. It looks like the shark skin that you get onthe props/shaft under the boat which I guess is mineral so acid should work if it can get to the offending areas.

Acids can be strong or weak (mild). Phosphoric is quite strong but weaker than muriatic. Concentration is another matter. It describes how much acid is in (typically) water. Phosphoric acid can be very concentrated, but I do not know the concentration in Ospho. Vinegar, acetic acid, or lemon juice, mostly citric acid, are weak and dilute. The latter two will dissolve most metal salts. They would be my first choice.

Since the application is in salt water and potentially warm to hot, I doubt there is any aluminum in the seal.... but if there is, it would not play nice with acid.

Bobk

 

[Boatsb]

Acids can be strong or weak (mild). Phosphoric is quite strong but weaker than muriatic. Concentration is another matter. It describes how much acid is in (typically) water. Phosphoric acid can be very concentrated, but I do not know the concentration in Ospho. Vinegar, acetic acid, or lemon juice, mostly citric acid, are weak and dilute. The latter two will dissolve most metal salts. They would be my first choice.

Since the application is in salt water and potentially warm to hot, I doubt there is any aluminum in the seal.... but if there is, it would not play nice with acid.

Bobk

I dont see an easy and safe way to get acid in there long term. It will run out into the water as its designed to do as cooling. I'd pop the carrier around and push water through to flush it clean. If it can be loosened up it should clear out the debris.

 

[Reefgeorge]

Just got off the phone

The bearing surface in the body is a teflon compound. The outer body is fiberglas reinforced thermoplastic.

The clearance between the shaft and the teflon "bearing" is 0.0075" plus or minus.

There are channels with more shaft clearance that run along the axis of the shaft that are tens of thousands.

The current plan is to try and push through those channels to increase water flow and reduce slip friction. Take some 0.005" material down and see if I can get around the whole shaft to keep cleaning it out. Force acid intothe body through the water fittings. Eventually block off the stern tube and move the assembly forward soI can see behind the body that is now obscured by the hose and also be able to really clean out the shaft log.

If this fails I will be circling the wagons for an in water swap out and considering a different system.

 

[Reefgeorge]

It looks like Teflon is very inert. It is resistant to all major acids at high concentration so that does not limit my chemical choices - just me, the shaft and the rest of the engine room.