Plastic stuffing box?

[Andy_P]

We've just got our hands on Fjord MS33 (1970s vintage). PO mentioned that the stuffing box would likely need tightening.
After a 1 hour motor it was dripping at about 3 drops per second. 24 hours later, it is down to 1.5 drops per second.
Either way, too much. I was about dig out the pipe wrenches when I noticed that this is not a traditional bronze stuffing box. Instead, two large plastic nuts are held in place with a cotter pin. An internet search turned up something similar (Teflon), with the advice that a wrench is not necessary. Apparently, the cotter pin is removed and the nuts can be hand tightened.

Does anyone have any experience of these, good or bad?
Does the advised drip rate differ from a bronze stuffing box?
You'll see in the picture that the stern tube enters the boat into a v-shaped space that is full of water. The water is not escaping into the bilge. I've poked around with a screwdriver and can't find a blocked drain hole. Any ideas as to what might be going on here?

Thanks in advance for any advice. We are away from our home port and I don't want to do anything that will alarm the admiral.

 

[jssailem]

Andy, the plastic (most likely nylon) part is inexpensive. It will have a shorter life than bronze but will not be susceptible to galvanic corrosion (a plus, but also not a worry, if you maintain the zinc on your shaft).

The number of drips needed is dependent on the temperature of the shaft seal. After it has been running, you should be able to touch it. (Caution: Do not attempt to check it while the shaft is turning.)

The area under the shaft log is a bilge. You can put a small pump in the space to empty the water.

 

[BigEasy]

We've just got our hands on Fjord MS33 (1970s vintage). PO mentioned that the stuffing box would likely need tightening.
Does anyone have any experience of these, good or bad?
Does the advised drip rate differ from a bronze stuffing

Had a similar packing gland on a 1988 Hunter 33.5. I owned the boat from ‘98 to ‘05. I did adjust it a few times, as necessary, using a stuffing box wrench to the point that there was no drip at rest & a few drips per minute while motoring. I was not able to adjust it by hand. I never replaced the hose; however, I did have to remove all of the packing & replace with new packing to prevent excessive dripping after hitting a submerged rope. I would prefer a traditional bronze unit; however, I didn’t have any problem with the nylon unit. Check yours for any signs of fractures & deterioration. Definitely check the hose, cotter pin, & clamps and replace if over 10 years.