Trojan Boat Forum

Ok,, it's time to repack shaft on my starboard motor, dripping pretty bad.

pros and cons to putting dripless in or repacking with traditional packings

besides expense difference
thanks

I use Gortx packing . Dripless is ok but when it leaks it leaks bad . Pros and cons to both .

I'm in the same spot with my 12M. I'm overdue to replace the bellows or change back to traditional types I currently have the PSS Dripless (been on there for a LONG time,) and I have to say that I'm very impressed. Not single drip underneath them.
However when they fail it could be catastrophic. I have never heard of a catastrophic failure on tradtional types. I think I'm going to switch it back when I pull the shafts out. I'm thinking since there is already a cooling hose (water injection hose) coming off of the heat exchanger to the PSS I might go with the Buck Algonquin model 8417300, traditional stuffing but with a water injection fitting.
Tom C.

I use goretex. Was going to upgrade to dripless, but my mechanic says dont bother uess you're also putting in new shafts.

My goretex had nary a drip for three years. Would often shoot my packing nuts with IR thermometer after shutdown, well, because i could. Would always be engine room ambient or cooler. Have never adjusted them, but i have a drip while at rest now, so thinking it's time.

P-Dogg wrote: ↑Tue Feb 19, 2019 4:43 pm I use goretex. … Have never adjusted them, but i have a drip while at rest now, so thinking it's time.

I also use goretex, but have left a slow drip anyway. I worry about corrosion and decided that some water movement at rest would help with that.

I replaced my flax packing with Gore GFO packing five years ago. It was the best thing I ever did. I have it adjusted so there are no drips when the packing is at ambient temperature and about 1 drop every six seconds when the packing is warm. In five years I never needed to readjust the tightness of the packing nut. The advertised lifetime of the packing is 10,000 hours so I'll never need to repack my stuffing box again. Simpler, cheaper, and more robust than a dripless system and almost as good.

My Trojan 350 exp came with NORSCOT dripless shaft seals. Great item. They work with three lip seals and a reservoir with ATF. The manual says seals should be replaced every 1000 hrs. I had boat on the hard two years ago and removed shafts for normal maintance and replaced the seals. NO drips.

Thanks for the input everyone. I probably stick with traditional , but go with the Gore GFO

P-Dogg wrote: ↑Tue Feb 19, 2019 4:43 pm.....Was going to upgrade to dripless, but my mechanic says dont bother uess you're also putting in new shafts.....

That's not always the case, it really depends on the condition of the shaft. With a lip seal type dripless system, the seal is made by stationary o-rings precisely fitted around the spinning shaft to keep the water out. As long as the shaft is true and the surface where the lip seals will rest is pristine, they'll work just fine even on an older shaft. If the shaft is true but mating surfaces are less than ideal, then the choice is to go with a face seal design such as the PSS or Duramax brands as they are more forgiving when it comes to the condition of the shaft surface. The newer Duramax design IMO is the better unit as they no longer use a carbon/graphite stator. In this design, while o-rings are still used, the shaft doesn't spin within them so it is more tolerable of a less than perfect shaft surface. The seals reside in a rotor that is clamped to the shaft and spins with it so the shaft is not spinning in the seal, this sealing is stationary. The main seal is made between the stator/friction ring and the spinning rotor that is fixed to the shaft. This is not accomplished with an o-ring but rather a perfect mating surface and water is kept out by surface tension of two surfaces pressed together.

There are pros and cons to both designs and both have their maintenance schedules. Neither design is install it and forget it!