pyi pss dripless shaft problem

[s/v Sweet Laraine]

I recently faced a mayday situation on the return leg of a day sail. Water covered the cabin sole about an inch. After checking everything I found the leak to be the two plates on the pss fitting. It took at least 15 to 20 attempts to "burp" the device with fresh water. I am concerned that this might happen in the future. Any solutions?

 

[Windborne]

Had a PSS installed last year by the boatyard during a haul-out. The installation instructions which they followed called for attaching a hose, mine is about 2' long, to the unit and securing it so it "stands up" vertically higher than the waterline to continually vents. Sort of self-burping I suspect.

 

[31seahorse]

Wow! Lots of water! How old is the "dripless"? We have had some leaking and some "burping" concerns, but those were on a dripless that we suspected was 13 years old and had been left unattended with the boat in the water for over 1 1/2 years.

I am interested in your post because we just installed a new dripless shaft seal and plan to launch this weekend if all goes well. Did you (or whoever did the installation) follow the instructions for positioning the rubber boot and then for sliding the stainless steel collar aft 3/4 inch from the spot where it just touched the carbon collar? Could the ss collar or the "boot" have moved? One forward and the other aft? If you need to adjust the ss collar there should be two set screws in each of the holes in the ss collar. The instructions are also pretty specific about how far aft you can place the rubber boot.

Solution: Reset the collar and the boot if the equipment is of reasonable age and if there is no obvious damage to the parts. Doing major changes or replacement in the water are not recommended by the manufacturer.

Best wishes.

Our old dripless did not have the air hose connection, but the new one does and is routed near the midline and above the waterline to prevent an airlock between the collars.

 

[Anonymous 121765]

SL,

When you fix your problem, here's a thought that will give you peace of mind.

After making sure you have the right amount of deflection between the carbon & rotor, you want to measure from the back of coupler flange hub to your PSS rotor collar (set-screwed). Depending on your shaft size, get & cut the PVC pipe to the measured length. Then cut it lengthwise into two halves. Install the two pieces around your shaft & secure with two S.S. hose clamps. Your collar will never slip.

I have never trusted setscrews by themselves in this application. My color slipped one time while out motoring. Now I can sleep better at night.

CR

 

[s/v Sweet Laraine]

Thanks, everyone for the interest. The factory rep suggested resetting the tension. Thanks, Capt. Ron for the PVC suggestion. I think that sounds like a good suggestion.

 

[windward54]

Or you can use a collar clamp to keep everything in place. MaineSail uses this one:


http://www.mcmaster.com/#acme-clamp-on-collars/=s6d0gj


PYI also has a version as well:


http://pyiinc.com/index.php?section=src&action=main

 

[JK_Boston_Catalina310]

A little thread drift, but does anyone else have a problem with a good amount of water coming out of the vent when in reverse? We stern into our slip so it's not uncommon for us to have the boat in reverse with a good amount of throttle on.

 

[Anonymous 121765]

SL,

Between Main & Stu, you can't go wrong on this site. Their knowledgebase & info links should fix any problems a sailor has.

I did my PVC fix before I joined SBO. Or, wisdom being hindsight, I would have ordered from Mainsail first.

CR

 

[jimmcgee]

PSS sells a retaining collar that does what Ron is describing. I bought mine after talking to a PSS rep at a boat show. It's a belt and suspenders idea, and because it's a split piece it can be installed without removing the shaft.

The picture I attached shows the retaining collar on the left of the shaft seal collar. http://www.pyiinc.com/index.php?section=src&action=main

 

[seadaddler]

PSS

To answer one question yes I did have water come out the vent hose when in reverse but since than I made the hose go higher and now have a bottle connected to the end of vent hose and have not seen any water in the bottle.
Yes some times the black rubber boot needs to be readjusted in 1/2'' or 3/4''.
Also I did need to clean the carbon collar and stainless collar with very fine sand paper in between the two of them for better contact and this needed to be done 4 or so years after install.
Some pitting got on the stainless collar the one with the set screws and this can be done while they are on the shaft maybe before readjusting and yes some water come in while moving the collar and sliding the sand paper in between and
turning the shaft while sand paper in between,I do have a stainless collar as backup also for extra insurance.
Nick

 

[John Nantz]

Retaining collar: Used a zinc

The retaining collar is news to me but sounds like a good idea. I've always just used a zinc - same one as what goes on the prop shaft near the prop.

On another subject:
With regard to longitudinal movement of the prop shaft, if one is under power with the prop pushing, the engine will move forward a little bit. This is a long shot, but the "little bit", depending one one's motor mounts, could be enough to lessen the pressure on the seal and allow some leakage. The accordion-pleated hose (that's what mine is) should be flexible enough to keep the pressure reasonably constant but maybe an older hose might not be as flexible.

 

[JK_Boston_Catalina310]

Thanks for the responses on the reverse issue.

To the OP's question, are you using new set screws after you readjust the SS collar? I believe these set screws are one-time use items.

JK

 

[Meriachee]

The collar should probably be considered "required". The little set screws are not enough to sleep at night.

 

[seadaddler]

Set Screws

PSS does recommend new set screws and can order new ones from PSS which
I did and I recently changed the rubber boot after the PSS been on my shaft
for 6 years and even still looked good but pulling boat for new bottom job decided to install new PSS rubber boot and also a new strut bearing also while boat was on the hard and added new longer vent hose higher and to a water bottle but have not had any water when in reverse.
Nick

 

[Rick D]

Piling on...

PSS does recommend new set screws and can order new ones from PSS which
I did and I recently changed the rubber boot after the PSS been on my shaft
for 6 years and even still looked good but pulling boat for new bottom job decided to install new PSS rubber boot and also a new strut bearing also while boat was on the hard and added new longer vent hose higher and to a water bottle but have not had any water when in reverse.
Nick

I have had three PSS installations on three boats over 20 years and lots of miles. The only time I had a leak is when a yard installed a new bellows and did not (I think) use new set screws. It slipped a bit. I have replaced the current bellows twice in 2500 hours. The old ones looked perfect, but I still did it for my comfort. I put a clamp in front of the bearing seal, but a collar is a far better solution.