Stuffing Box

Not sure of the proper name, but on my '79 my stuffing box look like a female/male pipe assembly held together with two bolts an adjustment nuts on the side. With all that I'm sure you guys know what I'm referring to. So, my question is about some of the many pics I've seen on this sight of stuffing boxes like mine. It looks as though someone cut the outside (larger) pipe in half an added a section of rubber tubing between the sections. Can someone explain what is going on. The reason is, I've got a knocking sound coming from somewhere in the shaft system. I think it is in the stuffing box; not sure. A setup like that may solve my problem.

Pictures would be very helpful, but I'll tell you right now that a knocking sound from a stuffing box would be pretty unusual. Maybe a loose cutlass bearing or transmission noise.

Ken

Agree there really isn't anything inside there that would cause any noise. An old timey stuffing box has only water and packing material inside it. Its built that way to allow some water to come into the "box" to cool the shaft, that's what the packing does. If its too tight, it gets hot, if too loose, too much water comes into the boat. Have to find the happy medium, but it should not make any noise.
Should add that the express reason for the stuffing box is to allow the shaft to pass thru the hull without sinking the boat. The packing or stuffing regulates the amount of water let in. Not really so much to cool the shaft per se as I said above. The heating or cooling is the affect created by the packing tightness.

Often the hard Stl Stl shaft will transmit sound from either direction- the prop or the reduction gear better than the surrounding material will transmit it. As mentioned there is nothing in your stuffing box other than the shaft, packing material and a little water. Do not take it apart looking for something knocking around.

Agreed photos of the stuffing box would help. I'm pretty sure I understand which type box you have but maybe the mounting is ?????.

Also agreed that there should not be anything to do with a stuffing box to cause a knock UNLESS the packing is literally worn out and the shaft is contacting the stuff box inside.

As suggested the shaft will conduct sound very well so something like a loose propellor could cause a knock sound. Also a loose shaft/gear coupling or shaft/trans coupling. Check it all out carefully.