Turn it off.
Let it cool enough to get the lock to come down.
Remove the lid and check the gasket for debris, etc.
Maybe even remove the gasket and rinse it well.
Replace the lid and turn it back on to see if it seals.

Is this the first canner load or has it already been heated?
Sometimes, if the water inside is very hot, I've had the lock engage quickly, but not really seal.

You can also wipe a very thin layer of oil on the gasket and that sometimes helps.

Hopefully others will chime in too.

Deanna

Okay, so I decided maybe there was something wrong with the lid lock, like maybe it was dirty or something, and I turned off the heat to let the canner depressurize. The lid lock went down IMMEDIATELY upon turning off the gas. But I'm looking at the lid lock and it doesn't seem to be dirty or blocked or anything. I unscrewed it and put it back in, and then I put the lid back on, and the lid lock tried to go up as soon as I twisted the lid on again. I have no idea what the problem is.

The lid lock is up? I think it will stop sputtering as the pressure builds. Is the pressure rising or is enough steam getting out to prevent that?

On mine the vent cover (weight) usually has a fairly steady drip coming out onto the cover. The lid lock should get all the way up there, but I guess it's possible that something's in the way (holding it open a little). If the pressure never builds, turn off the heat, wait for the lid lock to drop, open the canner to clean out the lid lock and inspect the gasket, then immediately restart the processing procedure (i.e. cover it and start building pressure again). Hope it smoothes out for you.

Melissa

Deanna, thanks! If it does it again, I'll use your oil suggestion. It's been on the gas for five minutes now, and it hasn't come up yet. (First time, it went on immediately.)

It was the first batch, but it had been brought up to heat once today already, as I was interrupted before I put my sauce into jars and turned everything off. Oh, shoot. There is goes again up. Well, it's not sputtering so far. Fingers crossed.

It's sputtering again. And I just noticed the overpressure plug is also leaking water. What the heck?

I'm turning it off, cleaning everything, and starting over. I'll oil the lid lock gasket. Should I also oil the overpressure plug?

Melva, yeah, the lid lock is up, but it didn't seem like any pressure built inside at all. So maybe I should vent for the ten minutes, then go ahead and put the weight on and see if it comes up to pressure?

Commonly happens and is a result of the heat in the metal itself. Bringing up to pressure at a bit lower stove temp helps prevent it.

It's no problem and no safety issue. Just let it continue and as the steam builds up and the air is evacuated it will quit bubbling around the lock and will seal tightly.

The lid lock is normally a bit of a vent in the beginning but oiling all the gaskets as well as the rubber sealing ring should be done regularly anyway. They dry out quickly so oiling them lightly before each batch is always a good idea and a good habit to get into.

dave

Thanks, everyone! I went ahead and dropped the weight on after ten minutes and it did come up to pressure, which I guess (?) is the crucial indicator that things are working correctly?

Dave, so this isn't unusual? Thanks so much! I was just sitting her thinking, "Okay, I've cleaned the gasket. What next?"

Wait, it was sputtering before it was under pressure? That was just because there wasn't enough steam to hold it up tightly. I didn't realize it wasn't weighted yet when this was happening. Mine will rattle up and down while it's deciding whether to pop up.

As Dave says, it's affected by how hot the stove is. I've found I can have a steady flow of steam out the vent and not have the lock come up until after I weight it to raise the pressure. In fact, that seems to give me the best results...if the lock comes up while I'm venting, I'm more likely to get siphoning.

Melissa

Melva, yes, this was when I first put thelid on. The lid lock popped up immediately started to sputter. I start counting my ten minutes for venting when the lid lock comes up, per Linda Lou. So I was surprised when it came up immediately -- it hadn't done that before. It had taken several minutes on high, and then when it did come up, it came up fast and shut immediately, without a long period of sputtering or putting out a puddle of water.

Dave, so this isn't unusual? Thanks so much! I was just sitting her thinking, "Okay, I've cleaned the gasket. What next?"

Nope. Not unusual. Sometimes it does and sometimes it doesn't. ;) But it seems to happen less often if I bring the heat up slower - notice it more when I'm trying to hurry.

It is just one of those things you learn to ignore as you get used to the PC.

Dave

Just a thought here -- how much water are you using? Pressure canners require only 2 quarts, and an abundance of water can sometimes cause a lot of sputtering to get rid of it.

gran2, I've been filling it to the first line, which is about 2" from the bottom of the pot. It's definitely tempting to put more water in since it seems like it's going to boil dry by the time it gets going, but I've so far managed to resist temptation.

What kind of oil do you use to lubicate the gasket?

I use mineral oil for gaskets (and also for lightly oiling cast iron before putting it back into the cupboard) because it won't turn rancid.

We just use canola oil for ours. Any kind of liquid vegetable oil will work as it steams off fairly quickly.

Dave

My 23 Qt Presto sometimes spits and sputters as I'm venting it. The lock always finally sets in place and stops the spitting once the weight is put on the vent pipe. Sometimes the lock does a little spinning dance first. :)

You always use 2-3 inches of water in the bottom of the canner, not so many quarts. The manuals are not always correct.
If you keep oiling that gasket, the sealing compound will get bad. The new compound should not be oiled unless you absoloutely have to if it is really hard to open.
I have never heard of a canner having the lid lock come up that fast. Seems odd to me.

When my lid lock seems steam and should have engaged but hasn't, I've found that my canner is picky about having the lid aligned just perfectly and when I shut the canner up hadn't rotated it to the closed position quit enough. One quick snap to the proper position usually 'rights' it. Yea, Valereee it's a pretty common occurance.

The manuals aren't always correct? That's scary. Yes, my 2 quarts was from the manual, both the cookers say the same even though one is a 4-quart and the other a 7-quart capacity. Only once have I had one go dry, and that was canning some kind of meat, I think, that processed forever.

Sorry to say, but the manuals are often providing misinformation. They even have some scary processing times in some I have seen. They make the canners, but don't have food preservation safety skills.
Do you mean they hold either 4 quart or 7 quart jars at a time or do you mean they are that small where they hold only that much water when empty ?

If you keep oiling that gasket, the sealing compound will get bad. The new compound should not be oiled unless you absoloutely have to if it is really hard to open.

That is good to know Linda Lou. I guess because we always replace our gasket every other year just to be extra safe, we have never noted any deteioration. Oiling is a habit we got into years back after we had the one PC lock up on us. Dynamite wouldn't have opened that bugger!

Dave

Linda, it seemed odd to me, too. I'm putting in an other canner batch right now, and this time I did NOT heat the canner (left it over low heat until I started to put jars in, then set it to high) ahead.

Hmmm...you know what I also did last time that I'm not doing right now? Last time I had the lid set onto the canner (but not twisted to lock it) as I was heating the canner up before putting the jars in. I wonder if that could be why? My water came to a boil just now and I set the lid in place and locked it, and the lid lock did NOT rise immediatly this time.

Valereee, the only thing that lifts the lid lock is the pressure inside the canner. So it came up because the water, steam, and air mixture inside the canner was heating up really fast. Heating the canner ahead of time would contribute to the starting temperature of the water, and covering the pot during heating would help retain heat to get the water hot faster.

So the behavior of the lid lock while the lid is closed is a function of the pressure, which is determined by the qualities of the air/water mixture and its temperature (since volume is fixed). Of course then we try to get all the air out to make the temperature more predictable as a function of pressure. But yes, the amount of pre-heating, and whether you cover the water during heating, will affect the starting temperature, and therefore the rate of pressure change just after covering it.

I've noticed some hysteresis in the lid lock behavior, by which I mean that it doesn't follow the same path during heating and cooling. This makes sense because, due to inertia, it's easier to hold the lock up than to raise it, so there is a point during heating at which the lock would stay up if you raised it yourself, but there's not quite enough pressure to get it raised. If you stay in this state too long you get more rattling with the lid lock. Then when it's cooling, the lock stays up at a lower pressure than what was needed to raise it originally, which is good for safety because it makes the processing time just a little bit longer.

Someday if stoves are completely electronic and computers have even more processing power, it would be possible to write a modeling program that uses numerical methods to solve the differential equations determining the heat transfer through the jars. Of course you would need to calculate the heat properties of the product, so this is probably even farther off than electronic stoves. For now empirical methods are so much easier, so we will keep telling people not to make up their own recipes.

Melissa

Dave, a gasket should last years. No need to buy a new one so often. I have used the same canner for over 30 years. I have only changed the gasket once in that time.
(As long as you don't oil them, they will last a long time.)
You check to see if it is pliable, no cracks when you slightly stretch it. If it is soft, then it should be fine. Only when they get hard and brittle or leak would you need to replace it.

Valeree, it does sound like you had it too hot that first time.

Linda Lou - capacity on my canners if 4 jars and 7 jars.

That 7 jar capacity may only be god for older Ball jars. Now that most have gine metric, the canners are sometimes not able to hold 7 quart jars anymore. That was what I just had problems with, so can only do 6 at a time now. As mentioned elsewhere, canning lids can dry out if they are more than abot 15 years old. Most all newere ones are silicone based and it helps to prevent the harding rubber compound. Boiling the lids prior to attaching to jars can also shorten up the seal life.

Can you restart a canner if in emergency had to shut it

Yes , if you had a problem like with the seal as discussed above, just cool it down , fix the problem and then start the process over. I had it happen to me recently. Tried to can some shell beans with a presto weighted gauge canner . the pressure came up but steam came out around the lid seal and the weight wouldn't jiggle. I just cooled it down , took out the lid gasket (seal) and wiped the crud / film off of it . then started the process over. Then it was all ok.

OkieHU