Stuffing Box- How long to repack?

[moguls2go]

Hi Guys-

I'm going through a work list with a local yard and was quoted 2-3 hours per side to repack stuffing boxes. This seems really high to me, but I've never done it. Looking online it seems like 30-60 minutes tops per side... thoughts?

[CaptPatrick]

Max,

Boat yards, not unlike auto service shops, have labor rates for individual routine jobs based on past experience. Most are covering their ass by using what they think is the most time a job may take, from the time the job order is picked up to the time it's turned back in as completed...

You're right that repacking stuffing boxes on a B31, especially when the boat is out of the water, is an easy and fairly fast job. If they allow you to work on your own boat, consider doing the job yourself.

[Howesounder]

I have re packed pump and boat shafts many times. I do the pumps for a living, and boats because I can. If a customer was to ask me, what you asked the yard,.... I would have replied as follows:

Depending on the condition of the packing, shaft, and gland, it will be "about" 1 hour per side. If it takes longer than two hours per side I will give you a call to let you know what we are finding.

Short answer tho is that 2-3 hours per side seems very steep.

Steve

[moguls2go]

Thank you! I've asked them to hold off and I'll do it myself in the spring time. Appreciate that guidance, as always.

[lobsta1]

Max,
A 3" drywall screw works wonders at digging out the old packing. Also, soaking the old packing helps a lot as it will be hard & crusty after drying out all winter.
Al

[IRGuy]

Al...

The same can be said about you.. as far as being old and crusty!

[Tony Meola]

Max,
A 3" drywall screw works wonders at digging out the old packing. Also, soaking the old packing helps a lot as it will be hard & crusty after drying out all winter.
Al

To add what Al said, if you have a Harbor Freight by you, they sell a small pick set, for a few dollars. I found them to be a great help.

[moguls2go]

Thanks guys. I've read that the last ring can be so hard it can be mistaken for part of the stuffing box itself. In terms of soaking the old material, do you suggest simply pouring a 5 gal bucket of water over the stuffing box?

[TailhookTom]

When you cut the new material for stuffing -- note that you really need to cut at angle so that when you wrap around the shaft the ends connect flush -- if you cut them off square the wrap around the pipe will result in something like a Stevie Wonder miter joint. Also, someone correct me if I'm wrong, but I believe you should alternate the "donuts" so the first one the buttjoint is up, the second the buttjoint is down, and so on.

Tom

[CaptPatrick]

How to pack shaft gland:

Most of the old Bertrams have a packing nut that contains the packing material. When screwed down onto the gland tube, the packing material is compressed around the shaft creating a water tight seal.

1. Loosen the lock nut on the gland tube.
2. Unscrew the packing nut from the gland tube.
3. Completely remove old packing from the packing nut.
4. With a length of packing material, tightly wind it around the shaft. Make sure to keep the packing tight and together.
5. With a fresh single edge razor blade, cut through the packing to create individually fitted single circles of packing.
6. Begin inserting, evenly, each circle into the packing nut. Screw the nut onto the tube to imbed the packing.
7. Unscrew the nut and repeat step 6 until you have a minimum of three pieces of packing stacked into the nut. Offset the cut joints so they don't line up...

For prop shafts, tighten the gland tight and then back off 1/8 of a turn. Final adjustment to be done in water. For rudder shafts, do not use Gortex or Teflon packing, only flax packing.

[TailhookTom]

Thanks Capt. Patrick -- I knew there was a more clear description of what I was trying to say!

Tom

[Howesounder]

Very important step that one about seating each ring to the bottom, and not just using the next ring to push the first down. On pumps at least, where there are 5-6 rings, if you just us the next ring to push the last in, you end up using too much pressure on the packing from pushing the other rings in, and it ends up too tight. I have seen a few pump packing containers literally smoke, and even light up on startup, even when the packing gland is backed completely off. It's just not possible to "un tighten" packing once it's been compressed into place. Probably more of a pump problem where the shaft runs fast on roller bearings, and has almost no run out. On a boat there is always a bit of wobble in the shaft, and slower speeds, so even too tight packing will get loosened up abit on startup. So each ring, Yep staggered, and set in to full depth on its own. Started up a fire pump once. Pumping from a pond with almost no suction pressure, so even when backed off we got very little water dripping at static. When this 3600 rpm, 150 hp pump started up, the packing smoke filled the room so fast we had a hard time finding the off switch.

Steve

[Pete Fallon]

Use only new flax packing material only. The Gortex stuff doesn't work well.
Pete Fallon

[Tony Meola]

Use only new flax packing material only. The Gortex stuff doesn't work well.
Pete Fallon

Pete

Please explain. I have been using goretex with good success.

[Pete Fallon]

Tony,
From past discussions with the faithful, the Gortex packing heats up very quickly and doesn't absorb sea water as good as the flax material,hence cooling properties is reduced. I tried the gorged packing when back in the early 80's and found that I only got 1 season out of it, compared to the flax packing which I got over 6 years before I had to redo it. My shafts were 1-1/4" Monel with intermediate strut bearings about 8" aft of the shaft log exit, these were the low profile shafts that came with the boat in 1961, the main struts were only 9-1/2" from the bottom of the boat. In 1994 I replaced the original stainless shafts with Monel, had new struts cast at Buck Algonquin ($850) for the pair, the barrels were cast bigger to be able to go up to 1-1/2" sheets of I ever went to diesels. The first of the early gas 31's had 102" aquamet stainless shafts that were snapping off at the log tube exits because of whipping old the long shafts, Bertram's fix was to add the extra strut bearing just act of the log tube. I never had any problems with my shafts except when I ran over a long line net that was just under the surface,hence, snapping the starboard shaft at 3300 rpms. I though the boat was going to jump out of the water when I hit that long line, never damaged the strut pad but bent the strut and snapped the shaft.Any Ialways used flax packing material after that one season in the 80's, just my take on flax packing.
Pete Fallon

[Tony Meola]

Peter

Thanks. I have found that a get a little longer life out of the GFO. After the repower, we packed it with Teflon coated. Ate that up in one summer with light use. Right now, it seems my Starboard shaft is eating up the packing faster than the port. They were repacked in 2014 and the starboard needs to be packed again and the port seems to run perfect. Go figure.

[Pete Fallon]

tony,
you should not be going thru packing that quickly. I would check your engine alignment, strut for true and check shaft for straightness.Also check coupler flange for loose bolts or missing keyway. Not too many places to go out of whack.
Pete Fallon

[Tony Meola]

Peter

That has all been done. Everything runs true. I have no vibrations or shaft wobble. The packing is a little tight going into that shaft for some reason.

[Pete Fallon]

Tony,
About the only other thing I can think of is the new packing the correct size for the shaft log and all of the old package is out of the packing nut and gland area .
Pete Fallon

[STraenkle]

Or just get the PSS dripless and be done with it.

[Tony Meola]

Pete

Correct size, tried going down a size but was too small.

Yes I have thought about going dripless but was trying to keep it to the Kiss method.

[ed c.]

I have been working on shafts since 1948 and there is only 1 way to take out the old material. buy 2 bottles of wine and use the corkscrew after you drink the first bottle to remove the material and open and drink the second bottle and remove the material. Repacking is very easy and should not take too long after you wake up. This should take about 3 or 4 hours. As for goretex I have put flax in 1 shaft and goretex in the other and I have not noticed much if any difference. Just my 2 cents.

[Tony Meola]

Ed

That is funny. Packing the gland is pretty easy. I usually do it while it is in the water. I don't get much water rushing in and I can usually get the first ring in place in about a minute or so after I get the last ring out. Once the first one is in you can go drink another bottle of wine before doing the second one.

I actually have had luck using goretex. It seems that since the repower the one shaft likes to eat up the packing.