Packing nut keeps backing off ...

[S/V Alchemy]

Originally Posted by captlloyd

By the way, I believe the picture showing the packing being wound onto the shaft is actually an improper way of installing the packing. At least not the way I was taught. I believe you make individual rings with the packing and alternate the cuts 180 degrees. That way the water cannot channel its way through the packing.

Correct. I've seen setups that take four rings (the diameter of the packing required can vary between 1/4" to 3/16") with the cuts orientated to six, 12, nine and three o'clock.

I made a blog post about it: https://alchemy2009.blogspot.ca/2013...fed-guide.html

[Cadence]

Originally Posted by captlloyd

By the way, I believe the picture showing the packing being wound onto the shaft is actually an improper way of installing the packing. At least not the way I was taught. I believe you make individual rings with the packing and alternate the cuts 180 degrees. That way the water cannot channel its way through the packing.

Packing wrapped probably acts as a screw thread.

[Djarraluda]

Originally Posted by S/V Alchemy

Correct. I've seen setups that take four rings (the diameter of the packing required can vary between 1/4" to 3/16") with the cuts orientated to six, 12, nine and three o'clock.

I made a blog post about it: https://alchemy2009.blogspot.ca/2013...fed-guide.html

I was always taught it is 3 rings, with the cuts at 120 degrees, 4 may be too thick and the pressure sleeve can not get into the outer sleeve adequately and the whole thing cants at an angle. Uneven alignment will cause uneven pressure, premature wear and possibly even metal to metal abrasion.
A big issue I found many, many years ago was someone had not removed the old packing, just added more. The bottom one was:
a) badly shredded; and
b) an absolute ...... to remove.
to make it worse, I was not being paid either.
Roger

[hamburking]

Are you certain its the nut backing off....could it be the new packing settling in? I would expect to need to tighten the packing nut a few times after replacing the packing.