Dripless

[Roland5048]

A hose clamp on the shaft, just forward of the rotor should keep it from moving forward, I should think.
Edit: Didn't read far enough into the article. The hose clamp trick was mentioned. I must have read that same article somewhere else. I know I didn't just think that up, myself.

 

[lee oakley]

Actualy a hose clamp sounds like a excellent idea easy and inexpencive!!!!

 

[kito]

Hey Lee, weren't you moving your H30 down to SC from Bath? Just wondering how that trip went. I am still waiting to get mine in the water

 

[Meriachee]

There's a proper collar that PSS sells for something like $20. You might want to consider that, it's far better balanced than a hose clamp.

 

[lee oakley]

Hey kitto no still a few more thingsto do to her first! How ya makeing out with your's? I have a gear cable to replace and change impeller also oil and filter

 

[kito]

I still have lots to do but it's basically ready to get wet. Just trying to find a hauler with a hydraulic trailer. The hauler I was going to use broke both his wrists in an accident and is laid up for a few months. Still debating on which body of water too.

 

[lee oakley]

ok like me seems nothing happensas fast as wanted! As far as water pemlico is great

 

[Ken13559]

There's a proper collar that PSS sells for something like $20. You might want to consider that, it's far better balanced than a hose clamp.

If one hose clamp can unbalance rotation then use 2 fitted in opposite orientation. That should balance it somewhat. Alot cheaper too

 

[Chris & Lenore]

So it seems that "operator neglect" accounts for 99% of the few failures that happen. With PSS, reusing setscrews, no safety collar and not replacing the bellows when recommended accounts for virtually every sinking.

FWIW, a tow/salvage operator here (Lake Ontario) says the majority of flooding/sinkings are from similarly neglected thru hulls or shore water connections. He has yet to see a PSS failure.

BTW the only shaft related sinking I know about was a traditional packing gland where the compression nut unscrewed and fell off. The owners left the boat on Sunday and Tuesday received a call that it had sunk. No shore power and the bilge pump ran the battery down.

So it appears that proper maintainence and visual inspections are the key - just like every other underwater component.

Chris

 

[dziedzicmj]

If one hose clamp can unbalance rotation then use 2 fitted in opposite orientation. That should balance it somewhat.

Provided that you have room for multiple clamps on the shaft. the PSS collar is much more elegant solution and at around $20 not that expensive.

One thing that the PSS collar has is a number (I think three) set screws with hex heads, so you can really tighten them up on the shaft. That way it really won't slip.

Marek

 

[alexco38]

The picture is a Tides Marine lip seal. The article is about PSS.
Not the same thing.

 

[capta]

A pretty old thread, but here's my 2 cents worth.
I was very interested in these until I realized that should one have a problem with it leaking, one had to haul the boat to change out some of the parts. Seems pretty impractical for a boat that's over 30' and actually does more than day sails or short coastal hops.

 

[uncledom]

How many thru hulls have taken a boat to the bottom? I like my dripless shaft seal. I inspect it as I inspect every thing else, weekly. Just found a broken hose clamp on the back side of the engine coming from the heat exchanger. Saw the engine bilge was wet which I would have ignored with the original packing gland. I really need to change out every Ideal hose clamp. Point is I might have missed this if not for the dripless.

 

[JamesG161]

Much of the responses have focused on failure or easy of repair. As always, you should outfit your boat to meet your sailing needs.

Failure of PSS...
No more likely than any another thru hull (less likely IMHO). Inspection is the key to all of them.

Ease of Repair...
Temporary fix...
All of the shaft seals mentioned in my post #16 can be adjusted while afloat.
Full fix...
I prefer PSS since I don't want to replace my shaft from wearing a groove.

You should always be prepared to manage any normal sized hull leaks, including a 4" hull breach. Even the world famous DUCT TAPE, will reduce water flow to a manageable level.
Jim...

PS: I have 2 pieces of 1/4" Starboard in different shapes. These have wood type phillips screws at the corners and are pre-drilled with just the screw tips exposed. Hull breach fix up to 12".

 

[Benny17441]

Here is one testimonial by a TowBoatUS operator about dripless shaft seal failures and sinkings:
http://www.passagemaker.com/articles/technical/running-gear/dripless-shaft-seals/

It caused me to go with the Norscot fitting.

I think the article was fair, it illustrated the maintenance requirements for a PSS and the need to follow manufacturer directives. It states that if properly installed and maintained it will do what the manufacturer claims it will do. To me it illustrates that if we were to install one that would be a need to change the outlook we may have about the traditional packing glands. I will admit that I am one not to pay the packing gland much attention other than monitoring the drip and I can readily accept a more frequent drip rate than specified. When it gets excessive then I will adjust it and eventually when it is likely long overdue I will replace the flex. I like it is all metal with no rubber bellows to deteriorate. The mechanical seal does not have the capacity to fail abruptly as could in a perhaps neglected PSS. The stated benefits of a dry bilge do nothing for me as I do monitor bilge pump cycling and can detect a problem quite fast. I find the scoring of the shaft is so minor that it can go decades without problems. Your boat, your maintenance program, your choice. No need to have heated arguments about what is best. They are just different and each will fit someone's needs better than others.

 

[capta]

The stated benefits of a dry bilge do nothing for me as I do monitor bilge pump cycling and can detect a problem quite fast. I find the scoring of the shaft is so minor that it can go decades without problems.

Over my 50+ year career as a professional mariner, I've never seen scoring of a S/S shaft by packing that I considered of consequence on any boat I've owned or operated. Nor have I had a catastrophic failure of a conventional packing gland, at sea or at the dock. The thought of a dripless one failing catastrophically at sea or when no one is aboard is rather sobering, IMO. I just do not see comparing well maintained bronze thru hulls with a dripless shaft seal.
If a 'dry bilge' is something one really wants, it can be had quite easily with a standard packing gland by catching the few drips they make in a sump with a small auto bilge pump.
I would hope we all monitor our bilges no matter what sort of shaft seal we use, so a leaking hose should soon make itself known.

 

[heritage]

I have seen wear of the prop shaft under the stuffing gland on my boat. Probably caused by over tightning the gland nut. Here is a pic from one of Maine Sails discussions: The link to the full article is here: http://forums.sailboatowners.com/index.php?threads/re-packing-a-traditional-stuffing-box.125430/ Notice that where the stuffing box wear is, there is also some crevice corrosion.

 

[All U Get]

Regular packing for us but easy to service because there is plenty of room. I use a Tupperware container under it to catch the drips while motoring. That way I know when to adjust. My wife is pretty handy with the therm gun and feels better checking the temps while we're offshore. The new drip less are for young sailors.

All U Get

 

[JamesG161]

I finally had a chance to read the article in post# 19 by Rbringle.
The article was well written and with many details that we have included in this post.

Major difference was a twin engine power boat!

The boat owner admitted he had done a major reverse thrust earlier. You want guess how much horsepower thrust were applied to the set screws? Not a bellows failure and leak was fixed while afloat.

This would indicate a need for the 'back up" clamp for BIG Horsepower auxiliary engines or if you want dual hose clamps. This was from my PSS maker...
http://www.pyiinc.com/index.php?section=src&action=main
After thinking about thrust forces a bit, I would like one similar to that link an to also prevent loss of shaft (rare). If you do add a clamp, make sure it matches the same metal as your shaft.
_________
I agree with Benny17441 post# 35 totally. This is not to show preference but to share info.

I am now brainstorming a bellows failure "patch procedure" and will pass it on if it is worthy.
Jim...

 

[JacksonvilleJeff]

I'm a big fan of Tides Marine dripless systems myself. Can't stand a wet bilge, and you follow the proper installation and maintenance (which isn't even very often), and you'll be happy. Here's some maintenance tips I stole from: http://citimarinestore.com/citiguide/tides-marine-shaft-seals-everything-you-need-to-know/

• Make sure there is never any blockage of the pressurized water feed to the shaft seal, and that the impeller is working well. It is vital to maintain a continual flow of water, and this is an important point that should be added to every maintenance checklist. If not, this can lead to overheating and possible wrecking of the shaft seal.

• Maintenance includes examining the lubrication system, hoses, clamps, and pump, on an annual basis.

• When performing maintenance, remove the water lubrication hose from the shaft seal. Make sure the fitting on the seal is clear and inspect for corrosion. If the boat is in the water, there should be a strong inflow of water from the slip into the boat. Use the inspection cap attached to the fitting to stop this inflow.

• With the vessel in the water, idle each engine. Check the water flow from the lubrication hose at the shaft seal. The flow rate should be about one gallon per minute at idle.

• Tides Marine recommends changing the lip seals every five or six years.

• Dirt, grit and fishing line can get sucked up if you run aground or operate in shallow, sandy bottom areas.

• If you notice a slight leak which steadily increases over time, immediately investigate further and resolve.

• If something ever hits the running gear, or if there are any alignment or vibration question, make sure you have your shaft seal checked as well.

• Should the boat need to be towed, the drive shaft should be immobilized or the engines allowed to idle to provide lubrication water for the shaft seals. If a crossover line is fitted on a twin engine boat only one engine need to be idled.

If you're not an expert though, have a seasoned and recommended boat mechanic install the seals and do the periodic maintenance....