It didn't sink!

[Mike Culik]

I replaced the propeller shaft packing on my new (to me) 1986 Hunter 31 in the water and it didn’t sink!

I cleaned the exposed shaft with 400 grit wet/dry paper in front of the plastic Morse stuffing box. I removed the compression gland nut and slid it towards the transmission out of the way.

Then after loosening the hose clamps I was able to slide the stuffing box enough to get the front plastic compression washer out of the way. Using a packing screw, I was able to pull the first layer of old packing out. Of course I had purchased the wrong size (1/4”), so after stuffing a rag in to the gland I was off to the store…..

After purchasing the 5/16” Gore-Tex packing and cutting to size on the cleaned shaft, I was ready to continued disassembly and replacement. I was able to get the stainless washer out by again sliding the gland and with the packing screw was able to get the second old ring of packing out.

You don’t want to waste any time at this point because there was a pretty steady flow of water coming in. After the first ring of new packing was pushed in, the flow of water was stemmed. Then I slid the stainless washer followed by the second ring of packing followed by the plastic washer. Fitting the compression gland nut hand tight and locking with the cotter pin was all that was needed to seal the shaft.

This all went together fairly easily. I bailed the water from under the engine several times with a sponge and bucket which was conveniently discharged down the sink. Maybe 5 gallons in all!

I started the engine and ran the boat in forward and reverse to check for drips…there were none and the stuffing box was cool to the touch.

Next project…120 Volt shore power panel rewiring…..I found that the old main supply line had melted at the main breaker!

 

[AtlanticAl]

Thats pretty funny doing a prop shaft re pack, with the boat in the water, wouldnt try it myself. But dont push it, when you do the electrical turn it all off first.

 

[Bill Roosa]

Did one too over the weekend

While draining the water tanks for the winter a guy just in from Boston was running around the docks looking for someone to help him "keep his boat from sinking" Seems that during the trip they did extensive motoring and the prop shaft gland had begun to leak. He did not know if he had the dripless or packing type so I agreed to go have a look and see if I could advise on what to do next. He had a packing gland and the nut was rusted on. When I asked when was the last time you adjusted it he said that in 5 years he had never done a thing to it. A testimate to packing glands IMHO. Well he did not have the large wrenches so, being a kind soul I suggested that he go out a buy them. I returned to de-watering my boat. About an hour later he shows up at my boat asking how to replace the packing. To make a long story short I did the job for him. When we took the packing nut off and the water started coming in it was only about a gal/min. He was on shore power and concerned that his batteries would be discharged by the bilge pump running so much. He also did not know the righty-tighty rule on threads and lots of other stuff.
It was pretty much a non event as far as the water was concerned and I'm glad I did it on someone eleses boat first. I would be very confortable doing it again.

 

[Ed Schenck]

Those plastic stuffing boxes must be different from what I am used to. There are no hose clamps to loosen on my bronze stuffing box. In fact I always try to tighten the ones on the hose before I start.

 

[Warren Milberg]

I'm guessing the reason Mike loosened the hose clamps was to enable him to push the whole gland forward (not just the compression nut) in order to remove the compression washers inside the OEM white plastic gland. See pic below of what the interior of this gland looks like.

IMHO, these plastic glands are a real PITA and I didn't trust the one that came with my boat as repacking it was just too hard. I recommend replacing these plastic glands with a conventional bronze gland that is quite easy to service and probably much stronger over the long haul.

 

[Nelsonhow]

Two observations:

1) It's not that you can't repack a stuffing box when the boat is in the water but what do you do when, as always happens things don't work exactly as planned, like nuts freeze, thinkg jam, hoses split when as you put it back together and parts fracture.... It takes experience and nerves of steel to voluntarily remove something below the waterline especially when you're on a mooring.

2) My expereince with plastice parts, even ones infused with nylon and other exotic materials is that when they are exposed to sun, fumes, chemicals they invariably become brittle and fracture. I think it's silly to make a critical part such as a stuffing box out of plastic. Give me BRONZE anytime for below the waterline.......

 

[inarathree]

A friend of mine owns a marina where commercial fishing boats are serviced. He says they replace thru-hulls and underwater stuff all the time with the boats in the water. He says thats what bilge pumps are for.

 

[RonRelyea]

I did it in the water

The PO of my boat had a shaft saver installed and therefore had no room to back off the gland nut to re-pack .... this is a "before" picture .... Without being able to re-pack the stuffing box, they adjusted it as much as it could go and let it leak! Look at the rust!!! I was able to remove the shaft saver and repack the stuffing box while in the water. Uneventful, except it was a BEAR to get the shaft saver off with next to no clearance. Copious amounts of PB Blaster every day for days in advance helped too.

 

[Mike Culik]

Nerves of steel maybe… some pre-planning and a lot of good information (packing material – Gore-Tex GTU, pictures, etc.) and unfortunately bogus and negative information (can’t be done, boat will sink, etc.) from fellow sailors is all it takes.

With pre-planning contingencies were in place for the anticipated and unanticipated …simply the boat yard was available to pull the boat.

Would I do it again….yes, but the preference would be when the boat is out of the water and a more leisurely approach could have been used. Pulling the washers and the packing was no big deal even with a little water coming in.

I was surprised the drive shaft was bronze and not stainless steel……

 

[Cherie320]

So like the other folks said.....not nerves of steel.....just good planning! Not too dificult to repack a brass stuffing box while in the water. A rag wrapped around the shaft and held against the gland will slow the flow to a trickle. Use a long zip tie in an X patern to hold the rag in place. Or you can tie it with a line and practice your knots. Have a plan for digging out the old packing. The corkscrew tools look like the ticket, but do not work well. A sharp right angled pick of heavy stock, 1/8-3/16" dia works OK. Think big dental pick. A set of small right angle needle nose pliers might be a good solution, but I've not tried that approach. Have the manual bilge pump ready to go with the handle installed and someone to pump it. It's a good backup to the electric pump. If you do not know the correct size packing material, have available for use,the size you think it is as well as one size larger and one size smaller. Packing is not expensive and you can always give what you do not need to a friend. I would not run to the store for packing after finding what I had was too small. Install the smaller size. That will limit the flow to what your helper can control while you are shopping. Then you can go to the store, get the correct size, start over, and repack with the right material. After you run in the packing, check and see if the gland needs a bit more tightening. We check it before and after each use when we open and close the engine raw water thru hull.


Search the web for examples of how to do this. Lots of folks have very nice writeups with pictures that address the important issues.

Caution - if the stuffing box/gland is in poor condition, except in an emergency, you should likely not repack in the water.

And just a thought - a shore power pump - 120Volt sump pump can be a good backup to your boat bilge pump. Pick one up at the hardware store and don't forget an extension cord. You could save your or your neighfor's boat with it.

Cheers, Pat