I have recently had my shafts' "stuffing box" repacked and then retightenend. Prior to the retighting the stuffing box was taking in a few gallons of water per outing. After the retighting the leaking stopped for a couple of outings but seems to be leaking once more. Is it too much to expect a dry bilge on a '79 Cat 30? If so, how much seepage should be expected/acceptable? Where should I expect to find the major water intake? Jax MB/SD
Dry Bilge
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Normal
It is the nature of the packing material not the age of the vessel. With standard impregnated packing flax, the compression on the stuffing box should be adjusted to permit 1-2 drops of water per minute with the shaft stopped. At this rate the water should evaporate before it gets to the bilge when the engine isn't running. When the shaft is turning this rate will increase and you will accumulate some bilgewater. After the shaft has turned a lot, the rate will continue to increase, requiring further adjustment. As the material ages under comression, this occurs with increasing frequency until it needs replacement. This task can be none in the water. The box should never be so tight that it stops the water flow since water is the lubricant that reduces heat from friction and wear on the shaft. The test is that after a few minutes of running, the stuffing box should be a little warm but not so hot that you can't hold your hand on it (while the shaft is stopped!!!!) Gortex packing is available at a very reasonable price and can be adjusted so that there is no drip at rest and very little under power. It doesn't heat up and it doesn't compress as easily requiring far less adjustment and rare replacement. You should be able to maintain a perfectly dry bilge. PSS makes a drip-less seal that requires a haul out to install and runs a couple of hundred dollars. It has a few idiosyncrasies to observe, but has a superb track record. I've never heard of a documented catastrophic failure of one of these seals, but, in theory, if it occurred it could sink your boat.
It is the nature of the packing material not the age of the vessel. With standard impregnated packing flax, the compression on the stuffing box should be adjusted to permit 1-2 drops of water per minute with the shaft stopped. At this rate the water should evaporate before it gets to the bilge when the engine isn't running. When the shaft is turning this rate will increase and you will accumulate some bilgewater. After the shaft has turned a lot, the rate will continue to increase, requiring further adjustment. As the material ages under comression, this occurs with increasing frequency until it needs replacement. This task can be none in the water. The box should never be so tight that it stops the water flow since water is the lubricant that reduces heat from friction and wear on the shaft. The test is that after a few minutes of running, the stuffing box should be a little warm but not so hot that you can't hold your hand on it (while the shaft is stopped!!!!) Gortex packing is available at a very reasonable price and can be adjusted so that there is no drip at rest and very little under power. It doesn't heat up and it doesn't compress as easily requiring far less adjustment and rare replacement. You should be able to maintain a perfectly dry bilge. PSS makes a drip-less seal that requires a haul out to install and runs a couple of hundred dollars. It has a few idiosyncrasies to observe, but has a superb track record. I've never heard of a documented catastrophic failure of one of these seals, but, in theory, if it occurred it could sink your boat.
No drip
I have a '77 C30 and my stuffing box is tightened just to the point that there is no drip. It's been like this for 10 years so far without any problems. So far only once, ten years ago I changed the packing.
I have a '77 C30 and my stuffing box is tightened just to the point that there is no drip. It's been like this for 10 years so far without any problems. So far only once, ten years ago I changed the packing.
Jax, You may be taking on water elsewhere while sailing. My C-30 is a '78 and I just realized I take on salt water when sailing: the bilge pump-line outlet mounted on the lower transom gets partially submerged when the boat is loaded or moving (healing)...I noticed a stream of salt water entering into the boat inside the transom where the hose exits the boat. The sealer is probally 25 yrs old and has give up. I need to reseal it and also check the cockpit drains. When the boat is at rest they sit hign above the waterline so there is no water entering the bilge. PS. I bought the PSS dripless shaft sealing system- works great! Good luck! Rob
Thanks Gents:
I took her out and really opend her up last evening ~ she leaked like a colander. I suppose I am going to have to repack her with a leak resistant pack. Thanks, you guys are all great. Jax
I took her out and really opend her up last evening ~ she leaked like a colander. I suppose I am going to have to repack her with a leak resistant pack. Thanks, you guys are all great. Jax
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