Shaft dripless seal replacement - difficult in water?

EKM

EKM

Active Member
Feb 4, 2007
674
Beach Haven, NJ
Boat Info
2000 420AC
Engines
Cummins 6CTA
I have dripless seals in my 400 DA (v drives) and one shaft is leaking at idle. When the engines are not running, nothing leaks. This just started (or I just started noticing the shaft leak). I have an installed spare but wonder how hard this is to change out the old one due to limited space. Has anyone done this in the water and how difficult is it?

BTW, this is my port engine and last winter I noticed my aft port motor mount lower nut had loosened up and dropped about 3/8". I tightened this up which raised the motor.

I don't know if this is what caused the dripless to leak.

Or is it worth keeping an eye on the leak and waiting until I pull the boat in the fall?

Thanks....Ed
 
How nice to not have V drives with all that room. Is this really this easy (from personal experience?
thanks for the video.
Ed
 
That was interesting... but if you have "V" drives it would be much harder to access the seal...
 
It really is that easy with straight shafts! V-Drives shouldn't be too bad as long as you can reach them. The sea water won't be coming out faster than any bilge pump can handle anyway.

I assume that you do have a spare seal on the shaft now? Also, you may want to inspect the spare just to make sure it is oriented in the right position before you cut the old seal. Someone else on the forum discovered that his spare seal had been installed backwards in error - that would be bad...
 
"V-Drives shouldn't be too bad as long as you can reach them" Boy that is an understatement! I can barely do this on my boat and I've got almost 4 ft between the engines. This will be close to impossible on a 400DA.



Ed,

There are other considerations relative to the seal as well. You might read this thread:

http://clubsearay.com/forum/showthread.php?t=31575&highlight=seal+replacement
 
EKM said:
I have dripless seals in my 400 DA (v drives) and one shaft is leaking at idle. When the engines are not running, nothing leaks. This just started (or I just started noticing the shaft leak). I have an installed spare but wonder how hard this is to change out the old one due to limited space. Has anyone done this in the water and how difficult

Thanks....Ed
Click to expand...

Are you sure that it is the seal that is leaking and not the cooling water that is pumped to the seal by the engine? Perhaps there are some loose hose clamps, did you check them?
 
Shaft dripless seal replacement

Ed:
Regrettably, this is beyond the scope of most boat owners. When you do your research you will find that SR did not start installing a second shaft seal on each side until about 2003. So if the seal requires a replacement the boat will have to be hauled, the shaft pulled aft while the new seal is installed and an engine re-alignment will then likely be required. It's a job for a trusted marina.

I don't want to bear additional pain BUT, depending when that mount sent the port engine out of alignment, you might also have a bent shaft. This is also an assessment which requires real experience. If there is a bend in the shaft do not trust anyone to try to straighten it (which some shops will recommend). It will cause vibration and potential transmission failure down the road. Replacing the shaft with a new one is the most economical and satisfactory solution. I know someone who still regrets not buying a new shaft for $900 installed - his bent shaft was never fully eliminated.

A friend of mine had his seal fail while underway on his boat - a 400DA gasser. He caught the problem in time as the engine temp moved up, shut down that side, tied off the transmission on this engine and limped into harbour on one engine. He was on vacation and it took 2 days to get another seal and a day for the haul-out and install. This cannot be done in the water.

Good luck Ed. Hope this helps and please do let us know how it is resolved.
Warren
 
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My boat does have a spare seal installed and it looks like a very tight squeeze to get to the old seal. I have about 12" from the seal to the spare and need some sharp picks to pull the old seal out. It only leaks when the eng is running.

BTW, the starboard engine seal has been replaced prior to my ownership, so perhaps it was done in the water.
I know this is a tough question, but once it starts leaking, do I have some time to wait until winter? I'm planning one big trip to BI, NPT and Nantucket (guessing about 25 hours of running time). Choice is to attempt the repair now or wait and let the bilge pumps handle the water seepage during idle. I don't think it leaks while cruising.

So I guess no one has done this recently? Any shops I could call that may know if this is possible? I started taking Yoga classes last week to limber up.

Regards,
Ed
 
Time shouldn't be an issue-especially since it leaks only when running. She won't accumulate much if any water in the bilge at the dock so no concern there...

I'd keep an eye on it, enjoy boating and deal with it at the end of the season.

I'm a bit puzzled by the circumstances, tho...
The engine was out of alignment (due to the dropped mount) but didn't leak until you raised it back up- presumably closer to being properly aligned?
Seals typically leak prematurely from engine misalignment or shaft whip; so why it didn't leak when the engine dropped on it's mount, but did when you fixed it has me scratching my bald head a bit.

I wouldn't replace the seal until/when the engine is properly aligned. You'll risk chewing up another one.
 
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this should be the seal system in my boat...http://www.tidesmarine.com/displaykb1.php?FileID=2 Sounds like its best to wait this out unless the seal leakage changes. I guess I bring a hammer on the trip.

Article Title: StrongSeal Lip Seal Change in Water with Spare Seal Carrier
Keywords: STRONG CHANGE LIP SEAL REPLACE SPARE SEAL CARRIER WATER
Date Submitted: 2009-05-21
Category: StrongSeal
Times Viewed: 963
Submitted By: John Theed

First make sure your bilge pumps are working properly, because it is the prudent thing to do.

Next clean the area between the shaft seal and the spare seal.

Remove the 2 (or 4) screws that hold the Spare Seal Carrier together and set them and the carrier shells aside. Do not lose these parts as they are re-usable


Find the beveled edge on the retaining ring that is around the lip seal in the Strong Seal housing and push it towards the shaft. Now pull out on it gently and unwind it 2 times around. You will have to remove this from the shaft in order to slide the new seal into place.

Take a hook and pull the existing lip seal out of the housing or place a self tapping screw into the existing lip seal, keeping in mind that it is ONLY 1/2" (12mm) wide and use pliers to pull the lip seal out.

You will have some water coming in from the outside, but it should only be a few gallons at most.

Clean the Lip Seal pocket and push the new lip seal up to the pocket.

Reassemble the Spare Seal Carrier on to the propeller shaft making sure that the shouldered side is now facing the lip seal. This is the tool that you will use to seat the lip seal into the housing.

It would help if you could brace the housing of the StrongSeal using some wood or other means but DO NOT put it against the Water Injection Fittings, as they will snap off. This keeps the hose from compressing when you are pressing the lip seal into place.

Using a Hammer, tap the seal into place by hitting the spare seal carrier on all sides so as to press the seal in evenly. Once the Spare Seal Carrier is flush with the front of the housing, reinstall the retaining ring.

Remove and store the Spare Seal Carrier unless there is a second seal, otherwise re-install it with the shoulder facing the transmission coupler. Make sure you leave at least 1" (25mm) of space between the shaft seal housing and the spare seal carrier.
 
If you have been running with the engine misaligned, then this isn't just a lip seal replacement. Your entire seal body is worn and it is not going to keep the new seal centered so it is only going to last a few weeks even if you are able to change it.

I explained this is post #2 on the thread I referenced you to earlier.
 
I looked over the weekend and there is 4" from the front of the seal to the tranmission. Thats a tight squeeze....don't need to bring a hammer on the trip since it is not fitting in this space anyway.
 
Have someone check the leak when you are under way. You might be flinging salt water under the engine and trans. not good.
 
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