Shaft Seal Recommendations

I too like the PSS system if I was going dripless. But after dealing with A LOT of yachts with dripless issues and such, I'm starting to go full circle back to traditional stuffing boxes.

I ran a 75' MY 5300 nautical miles with traditional stuffing boxes which we packed with the goretex packing. I didn't have to adjust them even 1 time. They didn't drip, they didn't have an issue till a year after we got back to Fort Lauderdale. It's easy to pull all of the old packing out and repack in the water.

I personally don't like the tideseals and am getting a bad taste for dripless in general. I've had one tideseal lock up on the shaft and break the water hose off going into it and spray saltwater all over the engine room. On another boat, the tideseal started leaking with 800 hours of running time, it ate 60 thousands out of the shaft and we had to replace the shaft (they were only 1.5" shafts on that boat.)

That sounds like a good idea. Unless you go with a "real" seal with an inflatable emergency sealing option, those dripless things are just a bit too flaky in my opinion.

..X2..

Cap, same exact thing happened to me and nearly sank my 63' Predator. After this experience I vowed never again to use Tides.

Have a look at the Kobelco/Eagle EVK seals - very reliable and fairly idiot proof. Has an inflatable emergency seal and you fit a spare seal on the shaft so replacement doesn't require drying out. My last boat has been running them for 10+ years and they seem to need a new seal about every 5 - couldn't tell you how many hours but think in the 10s of 1000s.

I'm constantly amazed at how passionate and polarized the discussions and opinions are about dripless shaft seals, it seems everyone has either a horror or success story. All of them, when properly installed, will provide years of good service just as any of them will fail, often spectacularly, when not installed correctly or if they lose cooling water.

I've installed just about every make out there and while my personal favorite is the Tides, I understand the concerns about the lip seal wearing a groove in the shaft. I always scoot the seal forward (or aft) every two years or so to give the seal a fresh place to ride on and haven't seen problems with units 12 years old so far, knock wood! Conventional stuffing boxes also wear on the shaft just as bad or worse so I don't think that arguement is valid.

Judging from the picture above, I have to say it looks like you have (had?) a serious misalignment of the shaft inside the shaft tube which caused excessive side loading on the floating cutlass bearing and it finally seized on the shaft. Loss, or reduction of cooling water also can cause the same thing and we have seen engine zinc flakes and other debris clog the smaller diameter water inlet hose barb. We now install a fine-mesh strainer on the cooling water outlet ahead of the shaft seal and have not had a problem with cooling water loss since.

I can't tell for sure from that pic and you'd have to take the entire assembly off to measure but if the shaft isn't centered in the tube, any type of shaft seal will fail in short order.

Unless you need to replace the boxes, I'd just use GFO packing, run it dripless and save your money for some fuel.

No alignment issues whatsoever. The part that holds the seal froze against the shaft and spun around ripping the hoses and making the mess you see there.

As I said, I couldn't tell from the pic if the shaft was centered in the tube or not. I have seen a LOT of boats that the coupling faces were aligned dead on to less than .003", but the shaft wasn't in the center of the tube. The bellows hose on the seals allows some missalignment, but not much. I just refit an older boat that the struts had to be moved because of this (they wore out the old PSS seals and cutlasses in a years time and thought that was normal). Usually, for a cutlass bearing to sieze on a shaft it is due to either a loss of cooling water or missalignment. I've found many yards only crack the coupling loose to check tolerances and don't bother to check the shaft tube, ASSuming it is right from the builder and we all know that isn't necessarily the case !