I recently replaced the o-rings on a keg. The keg was originally bought as new, probably 3-4 years old, so still in very good condition. I didn't have an o-ring problem I was trying to solve, I was just changing them as part of a trial. I changed all the seals, but the keg was leaking air once pressurized from underneath the liquid post. I tried tightening (no luck), loosening and then re-tightening (no luck), swapped to another new o-ring with keg lube added (no luck). I grabbed an o-ring from a different batch and leak solved.
The other thing I noticed was in the tightening process of the post. Normally when tightening these posts, you can start to feel some resistance as the o-ring starts to compress before the thread bottoms out and the amount of torque required goes way up. With these new o-rings, there wasn't that feel of o-ring compression, it just was fairly low torque required until the very end when the thread was bottomed out.
I used my calipers and measured the o-ring thickness in several places. This of course is tricky since you're measuring a compliant material. But I took several measurements at different points of the new o-ring, plus other new o-rings from the bag and they were 2.4 - 2.5 mm thick. Measuring the old/removed o-rings, all but one of them measured 2.6 - 2.8 mm thick, and one of them measured the same 2.4 - 2.5 mm. Measuring another o-ring new in the bag from another batch, it measured 2.8 - 3.0 mm thick. So summary:
Has anyone ever found thickness dimension info on the dip tube o-rings?
The other thing I noticed was in the tightening process of the post. Normally when tightening these posts, you can start to feel some resistance as the o-ring starts to compress before the thread bottoms out and the amount of torque required goes way up. With these new o-rings, there wasn't that feel of o-ring compression, it just was fairly low torque required until the very end when the thread was bottomed out.
I used my calipers and measured the o-ring thickness in several places. This of course is tricky since you're measuring a compliant material. But I took several measurements at different points of the new o-ring, plus other new o-rings from the bag and they were 2.4 - 2.5 mm thick. Measuring the old/removed o-rings, all but one of them measured 2.6 - 2.8 mm thick, and one of them measured the same 2.4 - 2.5 mm. Measuring another o-ring new in the bag from another batch, it measured 2.8 - 3.0 mm thick. So summary:
- New leaking batch 2.4 - 2.5 mm thick
- Old/removed non-leaking parts 2.6 - 2.8 mm thick
- Other new/unused batch 2.8 - 3.0 mm thick
Has anyone ever found thickness dimension info on the dip tube o-rings?