PSS shaft seal

[Jeff Kaplan]

Just had old stuffing box replaced with PSS dripless system.  The water discharge hose was plumbed in to the heat exchanger,2", on a tee with the  zinc.  We took the boat around to my mooring today, into strong 20 mph head wind.  After maybe 30 minutes of motoring, I heard a loud screeching noise that lasted for several seconds, then quieted down and then started again, over and over.  The engine temp remained steady at 180*.  I went below to the aft berth, removed the cushions and found noise coming from shaft area.  When back at the mooring, I touched the shaft and end of PSS and they were too hot to touch.  I went back to the boat yard and spoke to the mechanic about it.  He said he would come out to the boat to see what problem was.  Once home, he called me and asked me to do an experiment, take out the zinc, put brass plug in place, and take the boat out by motor. His thoughts were that the zinc was blocking the water from traveling thru the heat X at a steady flow thus causing the intermittent screeching and very hot shaft and PSS.  Has anybody else experienced such a problem, and also, if you have a PSS shaft, where was the water hose discharged to.  All thoughts are welcome.  Thanks...Jeff

[DaveBMusik]

The original model had the air vent plugged. You just had to burp the bellows once when the boat went in the water. Newer versions called for a vent hose. These were typically mounted above the waterline near the centerline. Water would sometimes be pushed out the vent hose when in reverse hence a variety of plumbing solutions. Some of the solutions I have read about in addition to yours is a water bottle to catch the excess, running the hose to the inside of the stern so excess would go into the bilge and using a hyvent valve to allow air to escape but not liquid.
A simple interim solution might be to burp the bellows to allow water into the seal to keep it cool similar to the original model. That doesn't solve your problem but it might get you out on the water...

[bayates]

I just installed the hy-vent ($14 on Amazon)  so that I would not get water out of the vent hose when in reverse at over 1900 rpm. Works great. I would take vent hose off the HX and route it high into head area the add hy-vent.

Brian

[Jeff Kaplan]

Brian,  could you supply me with the hy vent part # from Amazon, I couldn't find it by searching hy vent.  Thanks

[DaveBMusik]

They come in different sizes. i picked mine up at Home Depot in the Heating / plumbing Dept.
http://www.supplyhouse.com/Taco-400-4-1-8-Hy-Vent?gclid=CPDz0LaHis0CFVdahgodLtMIfA

[Jeff Kaplan]

Dave/ Brian,

I see the taco hy-vent. did you just put the hose from PSS shaft onto the hy-vent and mount it in the head under the sink or some place else. Also, I know the vent is to release the air, but what happens to the water discharge from the hose?

[DaveBMusik]

I mounted mine under the head sink as high as possible. The vent has a check valve which, in theory, should prevent the backflow.
Water Music goes in the water on Friday and we shall see if it works...

[Jeff Kaplan]

Yesterday, I took the vent hose out of the heat ex. and just mounted the hose high in the engine compartment, problem solved. No water out of the hose, forward or reverse, no more screeching noise.  I have the hy vent on the boat, just in case.

[Mark Sutherland]

Hey Jeff, I'd double check whether the vent line is weeping or not at higher rpm.  I think mine typically spits water when I hit reverse to stop the boat when pulling into my slip.  I'd be skeptical that it won't spit water, and when it does, what's it going to get salt water on?  My main power switch got salt water all over it, so I replaced it.  In my case, I re-routed my vent hose to a breather fitting mounted high on my transom.  I've never seen the Hy-Vent, but it sounds like a simple solution if it works.  Let us know how it works. 

[Jeff Kaplan]

Mark, I spoke to the people at PSS and they know of the hy-vent method, actually approved it. When I put the boat in reverse, I had a friend check to see if there was any water intrusion, none.  I saw how you routed your vent, my questions is, the travel length of the hose to the transom vent is pretty long and up, how does the water flow that far and up to the vent? I like the idea, but it seems a far way for the water to travel. Let me know, I can add as much hose as possible and the vent is not expensive.

[captran]

The first time it happened I was in the Bahamas and was very concerned and spent hours poking around.  seems like in certain wave and angle of heel conditions, I would get a little air lock in the bellows.  burped it and it was fine.  now, just as a precaution, I burp it occasionally, especially after a rough crossing of the strait of Georgia.  that seems to have taken care of it.  also, just recently went ahead and replaced the old PSS with a new one, as it had been over 10 years.  nothing looked bad, but thought it was worth it.  while I was at it, replaced the shaft, as the mechanic said he thought it was slightly bent.  I had them give me the original, and rolled it on a level floor and sure don't see any "bend", but, Oh well, "B.O.A.T."

[Mark Sutherland]

Hey Jeff, it is a bit further to the transom, but as far as I know, it doesn't really matter.  I think the key is that the PSS simply needs the ability to "burp" (for a lack of a better word), hence the end of the hose needs to be open or vented somehow.  I'm not sure the distance matters.  I hated the idea of having the hose spitting under my sink and I just thought mounting a water bottle for it was just unnecessary clutter in the engine compartment or under the sink, so I routed it to my transom.  The breather fitting I connected it to is identical to the breather for my fuel tank. 

[bayates]

Just put the Hyatt-vent through its paces to a raft-up. We only got water from vent in reverse over 1900 RPM. I bought the adapters from Home Depot and installed. High under sink. Not a drop even at 2200. This should be one all do just to keep the salt out.