Just as an experiment you could try reducing the dose of coffee and see if that prevents choking the brew.

I don't think it's choking, it's brewing pretty fast, but I did try putting less coffee with completely unsatisfactory results. Grounds gushing out into the top section, very weak coffee. I am guessing the amount of coffee is "calibrated" for the right pressure

Isn't there a filter plate that goes on top of the grounds to keep them out of the top section?

Sorry, misspoke - coffee gushing out, not grounds

temchik wrote:Hi All,

- The pot starts leaking steam out of the mid section sometimes unless I screw the top on very tight. I don't pack the grounds and just level with my finger, I keep the threads and the rim clear of grounds but unless I screw the top on insanely tight it will leak. Sometimes it leaks so bad there is not enough pressure for the water to rise at all. Did I get a bad gasket with my new Bialetti? Should I try ordering replacement gaskets?

One more time - it is essential to ensure zero leak in order for moka pot to work as intended. It's because when under heat, air above water + water vapor expand, pushing the water and starting the brewing process considerably below boiling point. I did some measurements and in my case, water started flowing out of the funnel when temperature in the lower chamber was around 60-65°C and ended a few degrees below boiling point, so there was actually no need to cool the device after brewing (except to avoid bad smell due to remaining water vapor overheating the coffee grounds left in the basket). It was when I used it according to instructions - pouring cold water up to the security valve, not too fine grind and no tamping. Depending on those conditions, brewing starts higher or lower etc. Since it's not easy to ensure several variables to be always the same, result is a bit unpredictable - unlike with idiot-proof FP where indeed some talent is needed to screw the coffee

If there is a leak, there will be no pressure rise until water starts boiling - and result will be bitter coffee cooked at above 100°C

It's strange that we have 2 occurrences of leaking. Maybe there are indeed some manufacturing problems. As I said, I made an portable espresso device out of noname 1 cup moka pot, I'm using using espresso grind with tamping and I apply pressure around 9 bar with bike strut pump (the same type as Rosco is using for Portaspresso) and when tighten properly - it doesn't leak. And in normal usage of moka pot, pressure is a fraction of that

Another way to test is to order replacement gaskets and see if that solves a pressure leak.

If your moka pot leaks around the joint between the top and bottom, meaning the ring-shaped gasket is leaking, then check three things: 1) Is the gasket clean of coffee grounds?; 2) Is the gasket "rubbery", meaning supple and has not hardened from age and heat? (Since your moka pot is new, I'd expect the gasket to be in good shape); 3) Finally - a trick to better seal the two sections of the pot - wet the ring-shaped gasket before assembly. A few drops of water on the gasket before screwing the top and bottom sections together reduces friction of metal on rubber and allows you to easily screw the two sections together tighter.

Obviously, if the safety valve is leaking steam, then pressure is in the bottom of the pot is too high and you need to go to a coarser coffee grind and/or less coffee dose in the filter basket. Make sure you have not tamped or settled the coffee in the basket in any way.

Over more than 25 years use, I've found moka pots to be extremely reliable. As long as the gasket is clean and in good shape, the coffee is not tamped and is ground coarse enough, you will get the pot to work. I will say, my experience is with Italian-made moka pots. I can't speak to pots knocked off by manufacturers in other areas of the world - which may not be made to as high of standards.

I tested once opening pressure of the security valve and it was around 4.5 bar ... which equals to water temperature about 155°C ...

About temperatures...
We made this short film more than 2 years ago:

Yes, I'm familiar with it. Conclusions however can't be directly transferred from brikka to moka pot, because of different quantities of water and air in lower part (2 cup brikka is of the size of 3 cup moka and height of security valve - "nominal" water level - is different). So in the clip it's suggested to use hot water in normal moka pot to avoid brewing the coffee with too low temperature, while on the other side some people believe that hot water should be used to avoid overheating the coffee ... which I believe are both wrong for usual moka pot