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  Topic Review (Newest First)
04-22-2009 03:49 PM
captbillc thanks Main Sail-----i ordered 2 ft of 1/4 " of gore GFO from emarineinc . it is expensive $19.25 + shipping for a total of 26.85 , but if it works as well as they say it is worth it.
04-21-2009 07:21 PM
Maine Sail

Duramax is sold at Hamilton Marine and is a Gore GFO knock off.

A good test of knock off GFO products is to stretch the fibers. If the middle of these fibers are white and not gray all teh way through, then they are not made from the patented GFO fiber material.

Many companies are using GFO fibers with their own name on it but some are not. Besure you are getting the real Gore fibers when you invest in a knock off..
04-21-2009 03:14 PM
shaft packing

has any one used Duramax Ultra-X packing ? it is advertised in work boat, national fisherman, etc. supposed to be 5X more thermally conductive than flax. 300% less friction than flax. needs virtually no water for lubrication & virtually eliminates shaft wear. i don't know where to get it retail.
04-21-2009 02:32 PM
badsanta good thing I did not use flax!
04-21-2009 02:06 PM
sailingdog Also, greasing the flax may prevent water from getting in and cooling/lubricating the propshaft as it turns.
Originally Posted by JHJensen View Post

Introducing another lubricant into the flax is not needed as the wax in the flax acts as a lubricant and adding another element to the mix which may not be compatable with the elements already present.

04-21-2009 01:40 PM
Using grease with the flax......

Originally Posted by badsanta View Post
Are you not supposed to grease the flax?

Introducing another lubricant into the flax is not needed as the wax in the flax acts as a lubricant and adding another element to the mix which may not be compatable with the elements already present.

04-21-2009 12:07 PM
badsanta Are you not supposed to grease the flax?
04-21-2009 11:58 AM
Maine Sail
Your "mechanics"

Your "mechanic" has installed your packing incorrectly.

There are very good reasons for installing it in separate cut rings and I will try to explain.

1) The first ring on the male end of the stuffing box must sit flat against the male end with no overlap. This creates a much better seal at that end of the box so minimal water can get up into the female threads of the stuffing nut.

2) The idea behind cut rings is to allow water to pass between the shaft and the packing and not between the packing and the female threads of the stuffing nut. With overlapping rings it can pass on the outside of the packing MUCH easier.

By having the two overlaps, one at each end of the nut, allows water to enter through the male end of the box, pass up through the overlap, and into the female threads. The water then travels around the outside of the flax using the female thread valleys as a conduit and it then comes out the transmission end of the nut where the other overlap is.

This tracking of water outside the packing leads one to believe that they have a proper drip rate when in fact they may only be getting marginal water flow between the flax and shaft.

When the nut is overtightened tightened the flax is forced into the threads there by slowing the "drip rate" and giving the appearance to the "mechanic" that what he has done is correct, when it is not..

3) By installing flax as one continuous piece it can automatically "kock" (can't use c ock or the spell checker removes it) itself inside the nut when tightened and is very, very tough to adjust properly.

4) By overlapping you can not get as many true rings of flax inside the nut. Instead of three rings you may be relying on 1.5 rings of surface mating area as opposed to three.

Some yards employ good mechanics some employ mechanics who are to lazy to do the job right. I'd say you learned your lesson about the quality of the mechanics in this yard too bad it cost you a 1/2 hours labor to be show how to do it the wrong way.....

Remember boats are NOT the only pieces of machinery to use packing. Industrial pump applications also use packing and also use cut rings. This set of industrial directions specifically states "Never wind a coil packing into a stuffing box"

How To Install Packings
04-21-2009 11:58 AM
JimsCAL The single piece method may work, but I have always cut separate pieces by wrapping the packing around the shaft to get the correct length. I cut each ring at 90 degrees (don't think the 45 degree cuts are necessary), and as you said, stagger the joints when inserting them. I don't like the idea of overtightening and then backing off. I prefer to initially lightly hand tighten, then tighten as required when the boat is in the water.
04-21-2009 10:48 AM
c40eb My boat's manual states that when replacing the flax packing, cut one continuous piece at 10 1/4 inches and wrap that around the shaft.

I recently pulled the shaft and in doing so, looked into the nut...the old packing was one piece, and sure enough there is a gap at the beginning of the wrap as SD noted. Not sure if this would be a problem, but shows the point. Maybe, maybe not.

IF I was going to replace the packing, I would use the 3-4 piece method.

But, I just ordered a dripless shaft seal. Whoo hoo!
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