does propane go bad?

Propane is a by-product of petroleum refining and natural gas processing. Natural gas is processed to remove butane, propane, and ethane that can condense and damage pipelines.

I believe you are confusing propane with natural gas. Propane is processed and can easily be liquefied by compressing it. Natural gas which comes directly from the ground can not be liquefied by compression and has to be chilled to very cold temperatures to turn it into liquid.

Propane comes out of the ground and has been down there at least a million years. Just inspect the container.

Just as an aside I was given an 18 turn 4,000 watt Onan generator in 1988. It had last been run in 1982. A 20 lb bottle sat next to it. The hose was still connected. I pulled up alongside and ran jumper cables to the stator starter. Around 10 seconds later it was running smooth as silk. Propane has its drawbacks but storage and fuel quality isn't one of them.

QCMan wrote:
It probably does but my guess is that you will be dust by the time it does so don't worry about it. Your tank will go bad way before that.

You, Your children, and likely their children. If it does. nobody has lived long enough to find out the shelf life... I think the tank would rust out first. And .. Well that too is not something I'd worry about as they are designed to NOT RUST.

The greater danger is leakage. Or expansion/contraction.
The first is obvious
The second... When the tank gets hot the contents expand faster than the tank. this drives up the pressure and there is a safety pressure release so it does not go POP (Followed by BOOM as it ignites)

Thus you can lose contents over time. But even that is LONG TIME.

A few years ago I found a full 20 gallon tank that got covered under some tarps and building material. It had been there at least 10 years.
I used it our propane grill. No problems, worked great.

Go bad? No. BUuuut .......... if it was filled, in the south, in the summer, it might be filled with something with a higher percentage of butane which might not perform very well in very cold weather.

no

Depending where its stored you could wipe out or blow out the little rubber seal on the propane tank before installing it for use. I also do that before the guy fills it up. To me that's the first item to go bad on a propane tank.

Compared to gasoline, diesel, and most other types of fuels, propane actually doesn’t have an expiration date.
As long as it’s safely stored, you can use it at its full potency 10, 20, or even 30 years down the line.
The only limiting factor is the propane tank itself.

Recertification 10 yrs after Date of MFG stamped on Collar Ring..
Visual Inspection good for 5 yrs then repeat every 5 yrs