Soo, how tight should the stuffing box be.?

[Jesse]

A digital infra-red thermometer has made this chore a bit easier. They are handy for 0ther things as well.

[Alan Wheeler]

That's better Roy, now your onto it.
CSY, good point on the Study Hall. I must do some more work in those by the way. It has been sadly laxed lately.

[Roy M]

If it's hot, it's too tight. If it needs a digital thermometer, it's too remote. Simply let it drip to the point it's warm to touch with your hand. It's pretty simple stuff and doesn't require anything more than that, does it?

[Chuck Baier]

OK, Basic rule of thumb for stuffing box, at rest, one drip every 10 seconds. That should apply to anything that is not dripless. The Goretex claims you adjust till it stops dripping. You can do that but the drip should just stop at rest. Underway you should have a drip, whatever it is, and again no drip at rest. This is a tricky adjustment and you can very easily over tighten to achieve this so we leave the Goretex, which we have used for years, drip about every 15 seconds.

[gonesail]

for sailboats I think you may even be able to adjust the goretex so there is no drip while running. also depending on how close your stuffing box is to your transmission .. there can be a lot of heat that is transferred via the steel shaft that might give false readings with digital infrared.

[Inthewind]

As far as dripping goes, I have put new packing material in stuffing boxes and even when slightly tightened they did not drip. Sailboat engines turn at half the speed or less of a power boat and I feel they are just not going to overheat provided they are not tightened super tight. I think the dripping is more criticle on an engine that reaches much higher rpm's. They are not going to imediately burn up, when underpower just go back there and take a temperature reading with you hand, if it's real hot, loosen it up alittle. It's not rocket science.

[Therapy]

Originally Posted by Jesse

A digital infra-red thermometer has made this chore a bit easier. They are handy for 0ter things as well.

Cost?
.........

[GordMay]

You can get IR Thermometers for under $20, with units in the $50 - $100 price range, such as the Flike 62, being common, or you could spend up to several thousands of dollars.

http://us.fluke.com/usen/products/Fluke+60+Series.htm

Fluke 62 Infrared Thermometer IR Thermometer Fluke 62 Non-Contact Thermometers - on Sale at Test Equipment Depot

[Alan Wheeler]

I need to correct somewhat of a theme here. Gland packing has to leak to ensure it is lubricated. You should not feel any heat. If it gets hot, it is binding and serious damage to the shaft will eventually occur. Once the packing is wet you can tighten it till the correct drip speed is obtained, then you leave it to drip. The water will lubicate the packing and will stop any heat from being created. If you can feel heat from the earing/seal, it is too tight.

[Inthewind]

The new square type packing material unlike the old rope type has a special lubricant that insures the shaft will easily turn freely when snugged up. Packing material has improved over the years and the type I like to use is square. Three strands of this stuff with the waxy lubricant make it almost impossible to leak even when lightly tightend. Over time when it get some wear on it will start leaking then. All stuffing boxes leak but hardly ever with new type packing material installed even when lightly tightened. Stuffing boxes should not get hot, if this is the case, then it is too tight.

[Inthewind]

Here is the packing material that I use.
West Marine: PTFE Flax or TefPack Packing Product Display

West Marine: Drip-Less Moldable Packing Product Display

[Chuck Baier]

I repeat

Originally Posted by Chuck Baier

OK, Basic rule of thumb for stuffing box, at rest, one drip every 10 seconds. That should apply to anything that is not dripless. The Goretex claims you adjust till it stops dripping. You can do that but the drip should just stop at rest. Underway you should have a drip, whatever it is, and again no drip at rest. This is a tricky adjustment and you can very easily over tighten to achieve this so we leave the Goretex, which we have used for years, drip about every 15 seconds.

[Acoustic]

Originally Posted by Chuck Baier

OK, Basic rule of thumb for stuffing box, at rest, one drip every 10 seconds. That should apply to anything that is not dripless.

Please do not go by basic "rules of thumb" for adjusting packing. They are generally based on a NEW shaft with NEW packing and no wear!! Most of our boats are old and have shaft wear! Every marine expert also has their own suggested "rules of thumb" so who's is right?

All you need to know is to adjust for little to NO heat and the least drips you can get with little to NO heat! Every shaft will wear differently and every shaft will have a slightly different drip rate even when properly adjusted. Some may not drip at rest, even with traditional flax, and some will. The only measurement that matters is the spinning drip to heat ratio and this should be measured after about 10 to 15 minutes of in-gear shaft spin.

Originally Posted by Chuck Baier

The Goretex claims you adjust till it stops dripping.

Gore does NOT make this claim!

GFO is NOT 100% DRIP FREE and it DOES NOT claim to be!! Yes you can, in many situations, make it drip free at rest but it should still drip and run cool when the shaft is spinning.

In the Gore GFO marine instruction they just say to adjust it to the desired leakage. It still needs a little water to lubricate and this is usually less than a traditional based flax whether it be Teflon impregnated or parafin based lubrication.

If you're going to stay with a traditional flax based system the GORE GFO is by far the best flax you can buy. The white Teflon impregnated flax is NOT GFO! It is regular flax with PTFE instead of a parafin based lubricant only. GFO is blackish gray in color!

GFO Marine Instructions:

AFTER THE LAST RING IS INSTALLED, take up bolts finger tight. Do not jam the packing
into place by excessive gland loading. Make sure gland bolts are taken up evenly. STOPPING
LEAKAGE ENTIRELY AT THIS POINT WILL CAUSE THE PACKING TO BURN UP. Run
the vessel for 5-10 hours and readjust packing to get desired leakage.




Please note that it says DESIRED LEAKAGE!!!! Not "adjust for NO DRIPS!!!"

[Chuck Baier]

Sorry Acoustic, I have only been doing this for 35 years so it is always good to have someone teach me the basics.

[Acoustic]

Originally Posted by Chuck Baier

Sorry Acoustic, I have only been doing this for 35 years so it is always good to have someone teach me the basics.

Me too Chuck about 35 years...

Just wanted to make sure you were not putting words in the mouths of W.L. Gore as that stuff has not been around 35 years and they don't make the claim that it is drip free..