1998 400 DA Shaft Seal Education Needed

[hd2002hd]

The marina mechanic, who is no longer there, told me something about repairing the shaft seal and after looking at it I’m a bit confused. Port side shaft seal is leaking. I placed an endoscope to view. At idle there is a slight drip. At operating speed a bit of a spray. I was told that sometimes there are extra packing rings on the shaft that can be slid down into place and tightened. When I look at it with the camera it looks like a seal. I also notice a hose going into the housing right where the shaft goes into the housing. I assume there is a seal in there and not packing and the hose is water to cool? Can someone give me a little info on how this works? I assume once the boat is pulled they will have to slide the shaft down to change the seal or does it work in a different way? If the seal is changed is it automatic to change the bearing as well? Should I have both seals. Hanged since it’s out?

 

[Bt Doctur]

If it`s a shaft seal with water lubrication then the shaft must be pulled rearward to replace this type of shaft seal vs just loosening the shaft log nut and replacing the packing.

https://www.passagemaker.com/technical/troubleshooter-understanding-shaft-seals

 

[fwebster]

Sea Ray installed Tides brand lip seals on the 330DA and the 400DA at the factory, so unless you or a previous owner had them replaced with a different type of seal, you have lip seals. These seals do not have packing but it is possible that you have extra lip seals in a combination seal holder and seal driver already on your shafts.

However, the design of the Tides Dripless seals is such that a nylon or Delrin housing fits on the shaft to keep the lip seal centered. The lip seal keeps the water out of the boat until it is worn to the point that water passes by the seal. If you get inadequate lubricating/cooling water flow or ingest sand, mud, grit in the cooling water to the nylon housing, the housing wears and gets loose on the shaft. At that point and the housing will no longer hold the seal centered on the shaft and will allow the seal to wobble and leak. In almost all cases, this is the reason lip seals leak.

Replacing only the lip seal only will stop the leak for a while, but this is a short term fix if the housing isn't replaced. at the same time because the new seal will wobble on the shaft and will wear out quickly. On a 20 year old boat, if it is a keeper, you are probably money ahead to haul the boat out of the water and replace the entire Tides assembly with a new housing and a new lip seal. If you only want the leak to stop for about 12-18 months, then just replace the lip seal.

If you have the original seals which were called Tides Strong Seals, you should also consider replacing them with the later Tides SureSeal kist with crossover cooling.

Here is a link to the Tides website and an explanation of the 2 types of seals:

https://www.tidesmarine.com/shaftseals/sure_vs_strong.php

 

[hd2002hd]

Great info. I really appreciate it. The pictures are helpful.

 

[midexp]

Sea Ray installed Tides brand lip seals on the 330DA and the 400DA at the factory, so unless you or a previous owner had them replaced with a different type of seal, you have lip seals. These seals do not have packing but it is possible that you have extra lip seals in a combination seal holder and seal driver already on your shafts.

However, the design of the Tides Dripless seals is such that a nylon or Delrin housing fits on the shaft to keep the lip seal centered. The lip seal keeps the water out of the boat until it is worn to the point that water passes by the seal. If you get inadequate lubricating/cooling water flow or ingest sand, mud, grit in the cooling water to the nylon housing, the housing wears and gets loose on the shaft. At that point and the housing will no longer hold the seal centered on the shaft and will allow the seal to wobble and leak. In almost all cases, this is the reason lip seals leak.

Replacing only the lip seal only will stop the leak for a while, but this is a short term fix if the housing isn't replaced. at the same time because the new seal will wobble on the shaft and will wear out quickly. On a 20 year old boat, if it is a keeper, you are probably money ahead to haul the boat out of the water and replace the entire Tides assembly with a new housing and a new lip seal. If you only want the leak to stop for about 12-18 months, then just replace the lip seal.

If you have the original seals which were called Tides Strong Seals, you should also consider replacing them with the later Tides SureSeal kist with crossover cooling.

Here is a link to the Tides website and an explanation of the 2 types of seals:

https://www.tidesmarine.com/shaftseals/sure_vs_strong.php

Frank, I have a 1999 400 DA. Do you know what the life expectancy is for these dripless shaft seals? Just wondering if I'm on my last legs?

How about the other 400 DA's out there in the nineties time frame? Have you had to replace your dripless?

 

[midexp]

Sea Ray installed Tides brand lip seals on the 330DA and the 400DA at the factory, so unless you or a previous owner had them replaced with a different type of seal, you have lip seals. These seals do not have packing but it is possible that you have extra lip seals in a combination seal holder and seal driver already on your shafts.

However, the design of the Tides Dripless seals is such that a nylon or Delrin housing fits on the shaft to keep the lip seal centered. The lip seal keeps the water out of the boat until it is worn to the point that water passes by the seal. If you get inadequate lubricating/cooling water flow or ingest sand, mud, grit in the cooling water to the nylon housing, the housing wears and gets loose on the shaft. At that point and the housing will no longer hold the seal centered on the shaft and will allow the seal to wobble and leak. In almost all cases, this is the reason lip seals leak.

Replacing only the lip seal only will stop the leak for a while, but this is a short term fix if the housing isn't replaced. at the same time because the new seal will wobble on the shaft and will wear out quickly. On a 20 year old boat, if it is a keeper, you are probably money ahead to haul the boat out of the water and replace the entire Tides assembly with a new housing and a new lip seal. If you only want the leak to stop for about 12-18 months, then just replace the lip seal.

If you have the original seals which were called Tides Strong Seals, you should also consider replacing them with the later Tides SureSeal kist with crossover cooling.

Here is a link to the Tides website and an explanation of the 2 types of seals:

https://www.tidesmarine.com/shaftseals/sure_vs_strong.php

Frank, I have a 1999 400 DA. Do you know what the life expectancy is for these dripless shaft seals?

How about other 400 DA owners with boats in this time frame. Have you had to replace yours?

 

[hd2002hd]

After reading thoroughly I noticed the part about preventing the prop from turning to prevent seal damage. I immediately recalled an incident 2-3 years ago where the water hose on the port side water pump failed. I limped a mile or 2 on the starboard engine and then was towed into the marina. So, how do you secure the prop in this situation?

 

[fwebster]

Frank, I have a 1999 400 DA. Do you know what the life expectancy is for these dripless shaft seals? Just wondering if I'm on my last legs?

How about the other 400 DA's out there in the nineties time frame? Have you had to replace your dripless?

How long? If you are in clean deep water and avoid churning up silt and sand, and you have the cross over cooling lines connected, then the tides should theoretically last almost indefinitely. However, the lip seals are a synthetic material that will dry out and lose it flexibility over time. Practically, if your seals are past 5 years of age, I'd change the lip seals at a regularly scheduled haul out (just to save a midd-season haul out)....because you are very likely on borrowed time.

Down where I live in the real world, where we have a sandy bottom and skinny water around the best spots to anchor out like near barrier islands....and marinas are located up in lagoons, and bayous, I have been lucky to get 5 years out of the housings. Last year I got tired of the Tides replacement cost and changed to LasDrop seals and so far have been very pleased with them.

My experience over 22 years has been that when Tides seals begin to fail, you will first get a few drips underway. Then they drip underway as well as in the slip for a few hours. That is followed be a continuous stream under way with dripping in the slip. When there is a steady stream leaking all the time, it is time to schedule the haul out and order your replacement parts. From the first drips, to a steady stream, can take up to 18 months, so this doesn't need to be a crisis repair. But, now you know what to expect so don't wait too long.

One more final point.......I have closed sumps under my engines. MY boat will accumulate a lot of water that gets well up on the oil pans before the sump overflows and the bilge pumps can begin to evacuate the leaked water I bought a 500 gpm automatic bilge pump and mounted it on a piece of scrap fiberglass, with a 6ft hose, then wired the + & - to alligator clips. When a seal begins to drip, I put the little aux pump under the engine and clip the leads to the starter motor, which is the closest constant 12V source to the engine sump. This way, the little bilge pump keeps engine sump dry and the seawater leaking form the seal doesn't get to anything that matters.

After reading thoroughly I noticed the part about preventing the prop from turning to prevent seal damage. I immediately recalled an incident 2-3 years ago where the water hose on the port side water pump failed. I limped a mile or 2 on the starboard engine and then was towed into the marina. So, how do you secure the prop in this situation?

The best solution is to install crossover cooling on your shaft seals where there is a "T" in the cooling lines connecting the port and stud seal housings to each other. This way if you have to shut down one engine for any reason, the cooling water from the engine that is still running will supply cooling water to both seals and you avoid the chances of burning up a seal housing and lip seal.

The other concern is the dead prop windmilling the shaft and damaging the transmission on the side without power. If you have ZF transmissions, you can just put the transmission in neutral and idle back to your slip without damaging or overheating your clutches. Some other transmission makes need to be secured in some manner to keep the prop from windmilling and turning the output shaft while you return to your slip. You can secure the shaft with a line around the prop, a pipe wrench on the shaft or a wrench on the coupler bolts.

 

[ttmott]

Short engine out runs (several miles) will probably not damage either the transmission or seal assembly; longer I would be cautious and dog off the shaft. To further Frank's above notes regarding the ZF; the engine's drive into the transmission also operates the hydraulic pump, it is that pump that provides lubrication to the bearings as well as the hydraulic pressure to actuate the clutch packs. Without the engine running bearing lubrication is compromised so, limit free-wheeling to the best extent possible. The cooling water for the shaft seals is for the friction between the seal assembly's Delrin bushing and shaft; low rpm's such as for idling back will be acceptable. The 400DA's did not have crossover cooling for the seals; everyone should do this mod to add the crossover; even if both engines were nominally running the seal cooling line can become plugged especially in areas like where Frank and I have our boats. When replacing the shaft seal assemblies make sure the two cooling port style are installed.
Tom

 

[hd2002hd]

Well, mine does not leak in the slip and only a drip at idle speed. Progressively worse as rpm’s increase. I’m still not100% sure what seals I have but will look closer next time I get down there. I would assume they are whatever came standard on this model. I assume their is significant let difference in a seal replacement or replacing housing and all? I was guessing roughly $2000 for one side for seal only and would assume double w/housing. Is that a reasonable estimate for parts and labor?

 

[fwebster]

The Tides Sure Seal (new design) is $575 MSRP ea.

The haul out is a local cost, but is about $400

To change seals you will need to have the props removed, the shafts uncoupled and slid aft far enough to remove and replace the seals, then polish the running surface, connect and run the plumbing for the seal cooling lines and reassemble with the new seals. There will be approximately 16.0 man hours involved in the seal replacement. This is another local cost, but here on the Gulf Coast this would be in the neighborhood of $1600.

Hope this helps.........

 

[midexp]

Thanks for the feedback Frank. My 99 has the straight hose (as oppose to to the convoluted) , but they are not blue. Not sure that doesn't mean they are not Strong's. So I'm guessing original. No problems so far. I boat in Great Lakes and am very careful about going shallow.

 

[Bt Doctur]

might be able to revert to standard shaft logs and flax packing to save a bunch of money