# stuffing box repacking and flax size



## dreuge (Sep 18, 2009)

Hi,

I have a 1979 C&C 29 Mk1, and I need to repack the stuffing box with the boat in the water. I have already tightened it a few times with short term sucess. I plan to use an old sliced-open bike tube to wrap around the stuffing box while I am working on the repacking, but I want to minimize the time which I have the gland nut off. Does anyone know what is a packing size a C&C 29 would use? I believe it has a 1" shaft.

The marina at which I keep the boat is not conveniently close to a marine supplies stores so I am hoping someone familiar with a C&C 29 would know which size flax to purchase or which size is likely. Given a probable size, I may tempt to purchase several sizes (say 1/8, 3/16, 1/4 ) and try to arrange a return after the work.

I see that West Marine sells Teflon Flax and GTU Gore. But in googling GTU, I came across GFO Gore-Tex dripless packing (see www.gfopacking.com ). Does anyone have experience with GFO?

Any input into the size or even which type of packing material would be great. Thanks.


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## Gene T (May 23, 2006)

Don't worry about sinking the boat. If you have an automatic bilge pump it will only run every few minutes. There really isn't much water that comes in around the shaft. I would unscrew the nut and measure the packing, then snug up the nut again and go buy the packing. Probably 1/4 but possible 3/16. 
A small hook is handy for pulling the old packing but a small screwdriver works. The also sell a puller that screws into the packing and makes it easy. You could pull one piece out to get the correct size. It should still seal up good enough for a while with what is left.

I always had good luck with Teflon Flax. Read up a bit on how to do it. 3 pieces are generally used offsetting the cuts. I always liked to snug it up good and then back it off until it would drip a little. (not much dripping needed). Check the alignment while you are down there too.

Gene


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## SEMIJim (Jun 9, 2007)

dreuge said:


> I see that West Marine sells Teflon Flax and GTU Gore. But in googling GTU, I came across GFO Gore-Tex dripless packing (see www.gfopacking.com). Does anyone have experience with GFO?


Gore GTU and GFO are the same thing, to the best of my knowledge. I used whichever one WM sells. Works great. It's not entirely drip-less, however, just very low drip rate, once it's settled-in.

Sorry: Can't help you with the size.

Jim


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## JimsCAL (May 23, 2007)

Don't know about the C&C 29, but FWIW my previous 30 footer with a 1 inch shaft used 3/16 packing.


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## sailingdog (Mar 19, 2006)

the GFO is good stuff... I'd point out that under sail, the GFO packing should still drip slightly... it is drip "less" not drip "free"... and if you adjust it to the point where it doesn't drip at all, you're likely going to damage the propshaft.


dreuge said:


> Hi,
> 
> I have a 1979 C&C 29 Mk1, and I need to repack the stuffing box with the boat in the water. I have already tightened it a few times with short term sucess. I plan to use an old sliced-open bike tube to wrap around the stuffing box while I am working on the repacking, but I want to minimize the time which I have the gland nut off. Does anyone know what is a packing size a C&C 29 would use? I believe it has a 1" shaft.
> 
> ...


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## dreuge (Sep 18, 2009)

Thanks to ALL for their inputs. I am leaning towards the GFO packing. The link I provided above points to an out dated site where the "buy-now" link fails.

I read in other posts that e-marine sells GFO online. The site is eMarineSystems.com and select the menue item "Packing-Shaft".

The website has some useful info, in particular, a table of packing size for standard Buck Algonquin Bronze Packing Boxes. See this link:
 EMarine Systems Packing Shaft

I also talked to them over the phone. They claim that GFO can be used dripless but warned about over tightening. They suggest adjusting from the lose side, tightening the gland nut until the dripping stops (as oppose to over tightening and easing the gland nut).

Even though, I will still let it drip a drop or two per minute (Just to be on the safe side).


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## CalebD (Jan 11, 2008)

Here is the best tutorial on stuffing box repacking (if you haven't seen it already): Re-Packing A Traditional Stuffing Box Photo Gallery by Compass Marine at pbase.com Check out his other 'how-to' articles as many are just as thorough.
The correct size might be 3/16", 1/4" or even 5/16". I doubt it is bigger then that but it depends mostly on the shaft diameter and stuffing box size.
For my 27' Tartan with a 1" shaft it was 1/4" that fit the most snug.


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## Omatako (Sep 14, 2003)

sailingdog said:


> the GFO is good stuff... I'd point out that under sail, the GFO packing should still drip slightly... it is drip "less" not drip "free"... and if you adjust it to the point where it doesn't drip at all, you're likely going to damage the propshaft.


I've always held the philosophy that the stuffing box should not drip unless the shaft is turning. So I would want mine to drip once in a while when I'm motoring but not when I'm sailing.

I haven't heard of the GFO/GFU products, they sound good, I may try and get some. I still use the old waxy flax stuff.


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## sailingdog (Mar 19, 2006)

Whether the stuffing box should drip with the shaft at rest is really dependent on a few factors: 1) Number of rings of packing; 2) Type of packing material; and 3) How much friction you consider acceptable.

With traditional flax packing material, you may need to allow some dripping when at rest to keep the flax sufficiently waterlogged to prevent the packing material at the inboard side from drying out and scoring the prop shaft. With the GFO packing, this is not as necessary, but the box should still drip a tiny bit when the propshaft is turning.

Checking the temperature of the stuffing box while the propshaft is turning is a good idea. It shouldn't be more than about 15-20˚ warmer than ambient temperature of the water. Anything greater than that, you're probably risking scoring of the propshaft.

With all packing materials, but more so with flax-based packing, you should allow the packing material to absorb water for a while before adjusting. The flax-based packing, IIRC, will swell a bit as it absorbs water and adjusting the box before it has done so will lead to an overtightened box that will score the shaft.



Omatako said:


> I've always held the philosophy that the stuffing box should not drip unless the shaft is turning. So I would want mine to drip once in a while when I'm motoring but not when I'm sailing.
> 
> I haven't heard of the GFO/GFU products, they sound good, I may try and get some. I still use the old waxy flax stuff.


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## jackytdunaway (Sep 11, 2006)

Where can i get the Gore GFO? I am having a hard time finding it.


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## Maine Sail (Jan 6, 2003)

You guys are spending more than you need to.

Hamilton Marine sells Duramax Ultra-X for 1.68 ft in 3/16" PACKING ULTRA-X 3/16" SOLD BY INCH OR LBS 420" 176152

And in 1/4" for $3.00 per ft PACKING ULTRA-X 3/16" SOLD BY INCH OR LBS 420" 176152

Gore GFO from eMarine is $9.63 per foot in 1/4"!!!

I am VERY impressed with both Gore GFO and Johnson Duramax Ultra-X. What I am not impressed with is the knock off product made by Western Pacific Trading and sold by West Marine while similar it is not braided the same nor is it the same make up as Ultra-X or GFO.

Duramax Ultra-X is what I now use 90% of the time. Hamilton Marine sells it for next to nothing. The folks at eMarine a giving you bad advice on "drip free". Ask them if they plan on buying you a new shaft after it is eaten by crevice corrosion? The drips do more than lubricate they allow clean oxygenated water into the shaft log which helps prevent shaft corrosion.

BTW this shaft was set to "drip free" not "drips less". This particular shaft cost over $1500.00 to replace.....


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## Omatako (Sep 14, 2003)

Maine Sail said:


> Duramax Ultra-X is what I now use 90% of the time.


Good post as always Maine.

But I can't stop thinking that the product you recommend sounds awfully like a good quality condom.


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## jarcher (Jul 29, 2008)

Not trying to be a wise-a$$, but...

That stuff looks great, but if it is not going to be completely "drip free" what is the advantage? The bilge is still going to fill to the lowest level that the bilge pump can pump it out, about half an inch. Its just going to take a little longer to get there. Once its there though, you'll still have 1/2 inch of water in the bilge.

So I guess I'm missing the point.


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## tommays (Sep 9, 2008)

It will drip way less for a MUCH longer time without the need for as much service and replacement


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## dreuge (Sep 18, 2009)

jackytdunaway said:


> Where can i get the Gore GFO? I am having a hard time finding it.


Take a look at : Packing-Shaft - e Marine Systems at "http://www.emarineinc.com/categories/Packing%252dShaft"


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