PSS Dripless Stuffing Box Leaks!

[AaronJ]

Hi, does anyone know of possible causes and solutions for a PSS dripless shaft seal that slowly leaks? I have the collar pushed back against the bellows pretty tightly, so it's drips slowly now. When the collar was at normal position it dripped about once every few seconds. Could I sand down the graphite seal or is it time for a replacement?

Thanks,
Aaron

[Paul L]

Give PYI a call. They have good support.

Paul L

[sded]

PYI recommends putting a clean rag between the SS and the carbon and spinning the shaft. Be sure you haven't gotten any oil in the seal. I have also used very fine sandpaper (>#400) to clean the SS rotor. Don't sand the carbon.

[FSMike]

They really don't like oil. Anytime we've messed with them, we finish wearing clean rubber gloves and clean them with alcohol.

[moonrsn]

Get a rebuild kit from them. They don't coat that much.

[Blue Stocking]

How old is the unit? If you are having to push the bellows back more than about an inch from the "out of the box" length to get a seal, its time to replace it.

[delmarrey]

For a 1" prop shaft PYI recommends 3/4" preload. I just recently pulled my PSS and shaft. I noticed a little pitting in the seat area and I'll bet it from sitting so much. Mine sits on the hard 10 months out of the year and the PSS and has only been on for two years. If one were to use their boat often I don't think that pitting would be a problem. "Use it or lose it".

[Blue Stocking]

I have seen that pitting as you describe on a few boats, and wondered if it might be galvanic action thru the Allen screw and the shaft. I have 1 1/4" monel shaft and a Drivesaver, so installed a tied-in shaft brush. No pitting in ten years. Any thoughts?

[delmarrey]

Originally Posted by Blue Stocking

I have seen that pitting as you describe on a few boats, and wondered if it might be galvanic action thru the Allen screw and the shaft. I have 1 1/4" monel shaft and a Drivesaver, so installed a tied-in shaft brush. No pitting in ten years. Any thoughts?

My shaft, PSS collar and set screws are all stainless. I think................It's the lack of recycled fluids and air (acids) that cause the erosion. although, mine was very minor and I was able to polish it out with a rotary lapping table with a 120 grit..................._/)

[s/v Jedi]

You forget the carbon counterpart of the stainless collar. These two have an electrical connection and each conducts. They also get wet with raw water.

Mine has some corrosion but it isn't leaking. Sometimes it is seized a bit and one time it looked like it was seized good but then a week later it was loose again without me doing anything about it... ???

I think one can machine and lap both collars, I don't really see a reason why that can't be done?? It might leak a little after that at first, but some run-time should seat them again just like happens with a new set? Anybody got info about that?

I have a complete spare set and will probably install that during the next haul-out.

cheers,
Nick.

[cat man do]

Always wondered about the carbon bush and s/s on those pss seals.
I got these ones instead

[CAELESTIS]

Slip a piece of 150 grit sandpaper (grit to the stainless) while the engine is in gear, and let it run 5 or 10 revolutions. Also you should place a t-bolt clamp on the shaft, butted up to the stainless collar, and secure.

[GypsyHawk]

Yes I am a little late but just came across this thread while dealing with my own leaking shaft seal (only when spinning). Caelestis, what do you mean "place a t-bolt clamp on the shaft"? Why? When?

[CAELESTIS]

Originally Posted by GypsyHawk

Yes I am a little late but just came across this thread while dealing with my own leaking shaft seal (only when spinning). Caelestis, what do you mean "place a t-bolt clamp on the shaft"? Why? When?

There are two very small screws that hold the stainless collar in position on the shaft (additionally there are two screws on top of the "gripping" screws so they do not back out). Those screws are woefully inadequate to hold the collar over time. Place a t-bolt clamp up against the collar and it will not move.

[Pete the Cat]

As a delivery skipper, I have often thought of adding a surcharge for anyone who has one of these suckers. They always seem to be a problem. They leak they need to be "burped" they do not seal or they score the shafts. I have no idea why folks put these complicated devices on their couplings now that we have materials that will keep the water out and work without dripping like the carbon fiber or clay packing. Sheesh! I am goning to add a surcharge for deliveries if you have one of these as I always have to bail constantly and adjust them. Pain in the butt.