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bell ringer
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Discussion Starter · #1 ·
First let me say that I was a Navy Nuclear Trained Machinist Mate for 11 years and have packed many a pump.

I replaced my shaft seal with a packing gland this past week and installed it with 4 rings of DuraMax Ultra-X packing. At boat launch the gland was just touching the packing and water was of course running out of it, which I wanted to be sure it was getting water. The motoring trip from the yard back to the slip was about 1.5 hours and during that I tightened up the gland a couple of times and it was still dripping 1 drop/5 sec and was cool to touch.

In a perfect world I would continue to make small adjustment over hours till I was getting a 1-2 drops/min and the gland was still cool. But that wouldn't be possible for a few weeks and in the meantime that gland is just dripping away.

So I was thinking of tightening it till it stops dripping sitting here in a slip, making sure that I can still turn the shaft my hand and later when I get ready to get underway to loosen it back up some and then slowly make adjustments.

How do others do this adjustment when not motoring (for the dinosaur types still using packing)?
 

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Farr 11.6 (Farr 38)
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When I had packing glands, I would sit in the slip with the engine running in gear, and note the drip rate over a 5 or so minutes. I would then stop the engine, and make the adjustments and repeat again, and repeat again, etc. until I got to a rate that I could live with, and which was not dripping unless the engine was running.

The few times that I did this, I worked backwards from where you started, I would tighten the packing until it just stopped leaking with the engine off and make another 1/4 or half turn tighter. Then I would run the engine and see whether I had a 2-3 drip at least every minute (with Teflon packing). If it was dripping too much I would continue to tighten until satisfied. I would run the engine underway maybe 2 hours, check the drip rate, and then after 5-10 hours underway check it again since the packing seems to 'seat' and needs to be tightened a bit at some point.

Jeff
 

bell ringer
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Discussion Starter · #3 ·
I will probably let it drip while here in the slip as it isn't like that is any different that my old dripping shaft seal. I know from pump packing experience that getting in a hurry is just a way to destroy the shaft and/or burn out the packing
 
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bell ringer
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Discussion Starter · #5 ·
It is barely dripping now. Am just going to leave till we get underway next.
 

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3 drops/min x 60 min/hr x 24 hr/day x 7 days/week = 30240 drops/week

30240 drops/week / 600 drops/ounce / 128 ounce/gallon = 0.394 gal/week

It takes maybe 10 gallons of water in my bilge to hit the switch and run the pump, so I would not worry too much.

(Did I get the maths right?)
 
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