Dripless shaft seals [Master Thread]

[Emerald]

Whats wrong with a few drips anyway? [snip]

I find myself on both sides of this. I agree, what will a few drips do, but then after sitting closed up in the hot Chesapeake sun, I often wonder how much of that bilge funk came from critters that dripped in from the stuffing box. I've always figured that with our heavily critter laden water, and given that I flush the head with fresh water, that stuffing box drips was the contributor (not stale water sitting in the bowl. If you flush with Chesapeake water, you will get a foul smelling scum in just a few days). Any one else come away thinking stuffing box drip led to bilge stink? Of note, Odorlos works great at getting rid of bilge funk, which gets me back to thinking it's critters, and yes, I've made sure I'm not leaking from the holding tank/head/ and associated lines.....

 

[rwthomas1]

My stuffing box either leaked a drop every minute or two at rest or not at all. Underway one drop every 10-15 seconds. I can't complain about that, only where the salt water ended up.

I just heard from a fellow boater about a trick to keep the bilge nice and clean. There is a biodegradable degreaser called Marine Clean. Non corrosive and IIRC non-toxic, he adds a bit to his bilge when it needs it. Apparently nothing will grow in it and it keeps the bilge sparkling. I need to try it. I've used it plenty to degrease engine, etc. but not for that application. I will warn you, don't get it on your skin unless you want a dermapeel.....

RT

 

[Emerald]

Hi Rob,

is this the product you're thinking of?

http://www.por15.com/MARINE-CLEAN/productinfo/MCG/

I've used it, and it is good stuff. Of note, I've found all of the POR-15 products I've used to perform extremely well. I've done extensive automotive restoration type work, and the POR-15 paints are in a league to themselves when it comes to dealing with metal. It is imperative to follow the directions to the letter, but if you do, wow!

 

[ted_reshetiloff]

RT you maybe had your stuffing box a little loose it sounds? Mine would not drip at all at rest and underway only a drop about every 45 seconds to a minute. Either way certainly valid concerns all around and you wont hear me trying to talk you out of a PSS. Its certianly the way I will be going with my next boat. Yeah its another maintenance item, but so it the stuffing box. Repacking every 5 years, shaft log hose every 10? Does not sound much different than what the PSS calls for. And as for failures I dont really see how a scared skipper with a few rags could not stop or slow down the potential leak there during a failure of either set up.

 

[Loren Beach]

Still no drip

Perhaps time to revive this ahead a little bit.
We are scheduled to go into the yard next week for several bits of ($$) work. One chore is to replace the PSS Shaft Seal. I could replace the bellows and O rings with a kit, but for a little more money we can go 'new'.
A short vent hose will be added, since that is the only version they offer nowadays.

Since last summer, I have had to compress the bellows a couple of times to keep it from spraying and I worry that the internal spring is getting weak.
Since we are way beyond the time specified by the vendor for a second replacement of the bellows it seems best to do this service while the boat is out for a bottom job.

I still appreciate the detailed info in this thread from Maine Sail.

'May your bilge always be dry"

 

[supersailor]

Dry bilge good. PSS good. The problem I had with the log was the total knuckle bashing lack of assessability on the 34. I also had to cut down tool handles to fit. It's now been three years without a barked knuckle. My hands love my PSS.

 

[Kevin A Wright]

Since this thread has revived I will throw in my $0.02. I've never had a dripless seal being a firm believer in KISS. But a sailing buddy installed one many years ago since his wife didn't like bilge smells. Worked just great for a long time and they had a dry bilge.

Then one day it failed. Not sure what exactly happened to cause the failure but his style of seal used a quart reservoir of ATF fluid which had leaked out and gotten on the rubber bellows which then slid right off the shaft log. By the time I was able to get on board to help they had water up to your calf in the cabin. BTW stuffing rags in there helps a little, but not enough to keep you afloat for very long. There just isn't enough room go get a good seal with anything.

I was finally able to reach down in there and get the rubber back over the shaft log. But when I tried to tighten the clamps the rubber just bulged out. The ATF fluid had softened the rubber to the point it was like jelly. I managed to wire and brace the seal in place but it was still in danger of slipping off. Nearest haul out was a 5 hour motor away (upwind of course) and we luckily managed to get there just before they left for the day so got to spend the night in the slings 'draining' the boat.

Besides the mess the water in the cabin caused, it left a film of ATF fluid over everything below. Was like an icerink down there until everything was scrubbed down twice. Luckily the water never quite hit the tops of the batteries and the electrical system was undamaged.

So my $0.02 is if you want to have a dripless seal go for it. But DON"T get one that uses ATF fluid - especially if the rubber isn't compatible.

Good luck

Kevin Wright
E35 Hydro Therapy

 

[Loren Beach]

Since this thread has revived I will throw in my $0.02. I've never had a dripless seal being a firm believer in KISS. But a sailing buddy installed one many years ago since his wife didn't like bilge smells. Worked just great for a long time and they had a dry bilge.

Then one day it failed. Not sure what exactly happened to cause the failure but his style of seal used a quart reservoir of ATF fluid which had leaked out and gotten on the rubber bellows which then slid right off the shaft log. By the time I was able to get on board to help they had water up to your calf in the cabin. BTW stuffing rags in there helps a little, but not enough to keep you afloat for very long. There just isn't enough room go get a good seal with anything.

I was finally able to reach down in there and get the rubber back over the shaft log. But when I tried to tighten the clamps the rubber just bulged out. The ATF fluid had softened the rubber to the point it was like jelly. I managed to wire and brace the seal in place but it was still in danger of slipping off. Nearest haul out was a 5 hour motor away (upwind of course) and we luckily managed to get there just before they left for the day so got to spend the night in the slings 'draining' the boat.

Besides the mess the water in the cabin caused, it left a film of ATF fluid over everything below. Was like an icerink down there until everything was scrubbed down twice. Luckily the water never quite hit the tops of the batteries and the electrical system was undamaged.

So my $0.02 is if you want to have a dripless seal go for it. But DON"T get one that uses ATF fluid - especially if the rubber isn't compatible.

Good luck

Kevin Wright
E35 Hydro Therapy

That brand of shaft seal was not common around here even back in the day. In the 90's, when I was researching which one to install, the "face seal" on the PSS product seemed to be the best regarded.

 

[Kevin A Wright]

That brand of shaft seal was not common around here even back in the day. In the 90's, when I was researching which one to install, the "face seal" on the PSS product seemed to be the best regarded.

I don't remember when he installed that, but I think it was one of the first ones out for our sized boats, his was a Hunter 28. I'd certainly never heard of one before that. Was the 'latest and greatest' at the time. But I'm sure they've improved them a lot since then. He's since passed on and the new owner has replaced it with a regular stuffing box - didn't tell me the reasons.

Kevin Wright
E35 Hydro Therapy

 

[BillyT]

A word of caution from an engineer friend.

When you remove the old seal the shaft may be so corroded that it would be wise to replace it before fitting a new seal of any sort.

Let the boat bucks fly!

 

[Alan Gomes]

A word of caution from an engineer friend.

When you remove the old seal the shaft may be so corroded that it would be wise to replace it before fitting a new seal of any sort.

Let the boat bucks fly!

Pecuniam nauticam fuget!

 

[Leslie Newman]

I just replaced the bellow in the PSS PYI on my new to me E380 (owned since -01/18). They recommend replacement every 6 years and mine was just coming due. It was really not hard to do the swap. And the kit was only around $90 delivered. I have seen it for a little bit lower price.

With my boat the previous owner had re-powered with a Yanmar in 2012, removing the Volvo which he said always gave him problems. During the swap a new shaft was needed and he also installed the PYI PSS.

Some care must be taken to not scratch the polished stainless steel disc. And I did a little cleaning with 2000 grit sand paper on the shaft since the disc has internal O-rings that slide over the shaft. My shaft was in very fine condition. It is not rocket science performing the bellow replacement. Fact that you get no water inside means all of your fittings are nice and clean.

Everything requires maintenance. The bellow on mine was still looking like new after six years, but after removal what I noticed was it had lost its spring and probably wasn't pressing the graphite piece as tight against the stainless disc. But I had been getting no water seeping in. The standard packing type stuffing box is just such a PITA. All my previous boats over the past 35 years had the old style stuffing box and after a year of having the PSS I would NEVER go back.

Removing the old...


New bellow installed...

 

[Kenneth K]

Bonding of Prop Shaft?

Leslie,

I watched some PSS youtube videos after reading your post. I'm probably due for a bellow change too, at my haulout in April.

PSS shows a (larger, higher hp powerboat) with a plastic "drivesaver" similar to yours. I have a flexible plastic drivesaver on my shaft.



In the PSS installation video, the mechanic fastens a bonding strap to each half of the coupling to ground the shaft to the engine. Also, the Universal Owners Manual (p45) says, "To ground shaft to engine install a jumper lead from shaft coupling to engine or gear coupling capscrews," But doesn't specifically say that grounding is required.

I don't have a bonding strap on mine. Apparently, you don't either. Is that the consensus????

 

[frick]

My E 29 has tradition stuffing box with Gortex

Thanks for the input! The cheap way out would be to simply reuse the existing unit but repack it with GoreTex. The PSS is spendy but I do like the idea of NO water. Hmmmm.... I'll have to think about it. RT

I too have tradition stuffing box with Gortex. The Gortex is getting renewed this spring for the first time in 17 years of use.
It has been so fool proof that I would not think about changing to a newer system.

Also the only reason I am changing this year is that I broke by 1971 prop strut at the end of my season last year. So I have a new strut and a new prop shaft too.

Rick

 

[Leslie Newman]

I do not have a bonding strap. I did not do the initial install, but the system has been in place since 2012 and the shaft, prop, strut, etc all look fine. I'm in the camp of "If it ain't broke, don't fix it". The yard up in South Dartmouth that handled the re-power seemed like a top notch group. I got to meet them during the purchase as I drove up a few long weekends to get the boat ready to bring home. It was Concordia Company.

Mine has a shaft zinc that touches the stainless disc. I assumed this was like a safety, making sure the disc did not move forward. I did re-install the zinc, though my pic did not show that.

Here is a pic of before I replaced the bellow... Note the zinc.

 

[bgary]

Mine has a shaft zinc that touches the stainless disc. I assumed this was like a safety, making sure the disc did not move forward.

PYI, when I spoke with them last summer, recommend putting a locking retention-collar on the shaft in front of the disc to ensure it did not move forward.

PYI sells these: https://store.pyiinc.com/collections/shaft-retention-collar

20 bucks each, and (IIRC) they recommended putting on two.

I found these at McMaster Carr (about the same price): https://www.mcmaster.com/shaft-collars

Bruce

 

[supersailor]

Mine came with the bonding strap and a vent to keep an air bubble from forming during haul out. You should be able to get the strap from PSS.

Thanks Bruce for the collar tip. I was about to have to start looking for one and this saves me a bunch of looking.

 

[Leslie Newman]

PYI, when I spoke with them last summer, recommend putting a locking retention-collar on the shaft in front of the disc to ensure it did not move forward.

PYI sells these: https://store.pyiinc.com/collections/shaft-retention-collar

20 bucks each, and (IIRC) they recommended putting on two.

I found these at McMaster Carr (about the same price): https://www.mcmaster.com/shaft-collars

Bruce

Thanks for that info. I had not heard of these and $40 is fairly cheap insurance. Will order a couple.

 

[bgary]

$40 is fairly cheap insurance.

Yup.

I had a weird pattern of water in the bilge last summer... basically bilge was filling up within an hour or so when under power, and I suspected the dripless bellows was ... I don't know... loose? stretching? Despite the fact that there was no evidence of water around the dripless, it was high on my list of suspects.

Called PYI, and their recommendation was to remove the set-screws securing the flange, move the flange aft (to compress the bellows slightly, and increase the pressure between the plate and the flange), re-secure the flange with NEW set-screws (they said this was really important, and provided them gratis), and then install the two locking collars in place to be SURE the flange couldn't move.

Turns out, the water was coming in through rudder tube, apparently motoring at/near hull speed put water pressure into the tube that wasn't there at rest or when heeling under sail.

Filling the tube with grease (per Christian's guidance) made it go away.

But, at least, now I KNOW the PSS flange isn't able to move on its own... and it only cost me 40 bucks.

 

[Leslie Newman]

My rubber tube that is the vent for the bellows runs up and ties into the exhaust hose, so it cannot siphon into the boat. I had zero problems last year after mostly motoring all the way back from Rhode Island and then spending the weekends around the Chesapeake.