Disclaimer: These modifications do not necessarily correspond to the Original Equipment Manufacturer’s specifications. Any modifications you make are your responsibility. While I’ve made the following modifications to my canners, I cannot, will not and do not take any responsibility for you or your canners. (In short, know what you are doing so you don’t hurt yourself, your family, your house, your cat or the neighbor who likes to peep out her window to see what you are doing.)
I am going to consider three examples below and tell you what I would do, or in the second two cases, have done, to bring some old technologies into the present.
|In the picture to the left, you see an older Presto canner lid with an older-model vent tube. While I believe these vent tubes are still available, along with a newer-but-different weight, you might decide that you want to upgrade to a three-piece weight set.|
An All-American Canner Lid showing the Petcock, old over-pressure plug and gauge, from left-to-right:
|Here’s an older All-American canner with the petcock and the old-style over-pressure plug. That over-pressure plug is no longer made and the new one won’t fit. What do you do? So long as that over-pressure plug is still intact, it should be fine according to All-American, when I emailed them. (I left mine and it seems to have been fine for years now.) If you need to replace the over-pressure plug, the petcock can be used as an over-pressure device. You would then add a new vent-tube and weight in place of your petcock.|
A National canner lid showing the over-pressure device, gauge and pressure knob, from left-to-right:
|This National canner is certainly showing its age. It has an ancient over-pressure device and a pressure adjustment knob, that I’ve read was absolutely horrible to set correctly. Of course, the gauge is also a rusty mess. When I bought my small 12-quart National, it was in about the same shape as the one shown in the picture. I replaced that old over-pressure device with a new All-American petcock. The pressure adjustment knob, I replaced with the Presto 1058 vent tube and use the 50332 weight set. The gauge I replaced with a Presto 85771.It’s been working great for a couple years now.|
Again, I won’t recommend that you make modifications to any pressure vessel you may own, but this is what I would do, and have done, to mine.
Note: The last time I ordered the Presto 1058 vent tube, I did not receive the same 1058 vent tube I’ve always gotten. Apparently there is a new design, or the suppliers have messed something up. In order to work with the Presto 3-piece weight set, the 1058 vent tube must have a chamfered or beveled outside edge on top. The two that I received were flat-topped and DID NOT WORK with the 3-piece weight set. Please see my post on the refurbishment of my Presto 21-B Canner for a picture that shows the proper 1058 vent tube that Will work with the 3-piece weight set.