Shaft gland not dripping
- Thread starter Thalassa
- Start date
Pete the Cat
Sustaining Member
Yes. The boat guys are right. If it does not overheat, it is fine. I have always used the clay stuff to pack my traditional stuffing box (with Gore tek rings on either side) and gone dripless with it for 30 years and thousands of miles. Possibly yours was done this way by PO--don't mess with it. Check it occasionally for excessive heat and leaking. OK if it is warm. Not OK if over 140 degrees or so after half an hour. If it ever starts to leak, never tighten it more than 1/8 turn at a time. I never trusted the mechanical dripless units because you really cannot repair them offshore or without hauling the boat. Boatyards do not like to install the clay packing because it takes several adustments to get it just right, but once you have it dialed, it is very good.
Very interesting, thank you Pete! So far the maximum temperature of the stuffing box, after running 30' at 2k RPM, was 115 (a steady rise). At that point I throttled down, coasting back to my slip. Based on what you found I appears that I just could keep going. I was under the impression that no drip may result in shaft damage (too tight packing causing grooves in the shaft). Nigel Cader's ‘Boatowner’s Mechanical and Electrical Manual’ p547 (4th edition) mentions that it's possible/common to score grooves in the shaft, needing possibly a replacement. After the shop's repair (for excessive dripping) I noticed a clay substance under the stuffing box (see picture). This may have been the way they dealt with the problem by adding clay to the packing.
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From under the shaft gland.JPG
As usual, Rod Collins at marine how to has a great article on this topic:
I'm not sure if Ericson has a particular problem with getting air in the shaft log, but it's worth keeping an eye on.
One of the things I learned during my haul out was Ericson's use of monel steel instead of standard stainless for the shaft. The prop shop said its the reason I didn't have any significant ware on my shaft and why they were able to reuse instead of replace. Still just good piece of mind, but I wouldn't rely on that when deciding how to set my stuffing box (if I still had one).
Re-Packing A Traditional Stuffing Box - Marine How To
The Stuffing Box (click any image to see a larger version) While digging around in some old boat parts boxes I found a stuffing box from an older sailboat. I though it would be a good time to rig it up
marinehowto.com
I'm not sure if Ericson has a particular problem with getting air in the shaft log, but it's worth keeping an eye on.
One of the things I learned during my haul out was Ericson's use of monel steel instead of standard stainless for the shaft. The prop shop said its the reason I didn't have any significant ware on my shaft and why they were able to reuse instead of replace. Still just good piece of mind, but I wouldn't rely on that when deciding how to set my stuffing box (if I still had one).
Pete the Cat
Sustaining Member
That looks like the stuff I use. A bit of the clay could come out as the the seal seats. it is green with metal flakes in it when you start out but gets to look a bit brown when you grease it up with the Syntec grease (AKA in the boatyards as "elephant snot") that comes with the kit--costs about $70). I have put thousands hours on the shafts and no scoring and I have not needed to do anything with it once it is broken in. It won't score the shaft at 140 degrees or less with two good GorTek packing rings. Although they have improved the PSS shaft seal mechanisms from the first models, I was never comfortable with them after having a bellows fail off shore on a delivery. Obviously you cannot fix a PSS unit without hauling the boat and pulling the shaft--but they have improved the design in recent years with a better bellows and "burping" system. If you ever replace the clay stuff (and i would not mess with it unless you have a leak or heat problem), follow the directions in the box exactly--they are not complex--and do not overtighten the nut. I have installed the stuff on 3 boats. It takes a few hours to get a new clay packing seated so that it does not leak and does not get too hot (you hand tighten initially and then turn it up 1/8 turn untll you get no leak) and this is why boatyards generally prefer to put in the PSS product--much easier for them to install and more $. I just do not like them for offshore use. I have installed the clay stuff with the boat in the water. Nice to know you have that option if you had a problem. I learned about this from the lobstermen in Maine who have used it for decades.
A PSS refers to the PYI PSS shaft seal:
PYI Inc. | PSS Type A Shaft Seal
The PSS Type A Shaft Seal is a mechanical seal for 3/4 inch to 3-3/4 inch (20mm to 95mm) shafts.
www.shaftseal.com
It's an alternative to a packing gland and is one of many products that doesn't rely on sea water coming into the boat to lubricate the seal. Despite being in the market for decades, it's still a polorizing concept. I guess it hasn't reached the pivotal point that roller furler or spade rudders have. Maybe 2030 is the dripless' decade.
Pete the Cat
Sustaining Member
I actually think the PSS is a better option for most folks who mostly sail out of a marina and do not have a mechanical inclination. And I think they have become a standard upgrade out of boatyards these days because they are a simple install that requires no break in period and owner involvement in initial adjustment. Having one spew fine salt water spray all over an engine when I was 30 miles offshore left a lasting impression, but I was able to get to a boatyard with the usual help of a duct tape and a towel. I am an old fashioned sailor who wants things I can fix underway. I do not claim to be normal or modern in my views.A PSS refers to the PYI PSS shaft seal:
PYI Inc. | PSS Type A Shaft Seal
The PSS Type A Shaft Seal is a mechanical seal for 3/4 inch to 3-3/4 inch (20mm to 95mm) shafts.
It's an alternative to a packing gland and is one of many products that doesn't rely on sea water coming into the boat to lubricate the seal. Despite being in the market for decades, it's still a polorizing concept. I guess it hasn't reached the pivotal point that roller furler or spade rudders have. Maybe 2030 is the dripless' decade.