Shaft seal packing adjustment

[northern]

A few years ago I had the engine shaft seals repacked (They are the drip type) The leakage rate has increased and I would like to tighten the packing nut up a bit. The nut used to turn by hand and now it will not. The threads have thin film of green corrosion on them. Do I need to spray something like CLR or vinegar on them to loosen them up or just use big wrench? Leak rate has increased to 2 gallons in 8 hours of running from a quart.

 

[Bt Doctur]

spray the nuts, loosen the lock nut, adjust the drip rate, tighten lock nut

 

[sbw1]

Won't hurt to spray them but a good wrenching is ok too. The threads are harder than the green patina. Just make sure there is enough remaining packing in the gland to stop the leaks. I used to add packing while the boat was in the water when the leaks became excessive.

 

[fwebster]

The green stuff is just surface corrosion on the bronze and shouldn't affect your ability to tighten the packing nut, but shoot it with a light lubricant if you want to. The idea of the packing gland is to compress the packing so it swells and seals the area between the shaft and the packing gland. Try a large adjustible wrench...the packing nut should tighten with a bit of pressure on the wrench to the point that the leak slows to 3-4 drips per minute. If the packing nut is so tight that you need to use 2 hands (how is that for a touque limit?) the packing is dryed out and already compressed as far as it should be. If the nut won't tighten enough to stop the leak to 3-4 drips per minute on a 1-1/4" shaft, then it is time to replace the packing.

If your packing is original to the boat, then it is probably dried out and you more than likely need to replace it. Use Teflon or Goretex packing or order it from the manufacturer (probably Buck-Algonquin)....avoid low volume sellers and retail stores where the packing you buy may have been sitting on the shelf drying out for years.