The dictionary is your friend.
I'm not saying Googling the phrase won't help, but a more direct way to unlock the mystery of an idiom might be the dictionary.
I recommend starting at OneLook, which is a website that searches through several online dictionaries. As an example, when I enter all hell breaks loose into OneLook, it returns three or four potentially helpful dictionary links:

If you notice, links 3, 4, and 5 have the phrase in all caps. That's in part because All Hell Breaks Loose as been used as a title in various places, so we won't get much there. But links 1, 2, and 6 look promising.
In fact, all three of those provide decent definitions. Link 6 links to The Free Dictionary, which happens to be an excellent resource for deciphering idioms. It explains:
if all hell breaks loose, a situation suddenly becomes noisy and violent, usually with a lot of people arguing or fighting : This big guy walked up to the bar and hit Freddie and suddenly all hell broke loose.
The Cambridge Advanced Learner's Dictionary (Link 1) is written with the English Learner in mind. In this case, CALD and TFD give identical definitions, although the example sentence is different:
One policeman drew his gun and then suddenly all hell broke loose.
The meaning at Wiktionary (Link 2) differs some, but that's a good thing. Multiple definitions often help us get a fuller sense of the true meaning of a word or phrase. Wiktionary says:
all hell breaks loose (idiomatic) The situation becomes chaotic or characterized by conflict or rage
The OneLook results also provide a link to the Urban Dictionary. A note of caution about that resource: it contains a lot of slang, and it is neither compiled nor reviewed by a panel of experts. Still, it might contain a lot of phrases not found in conventional dictionaries (some of them quite vulgar). It has its place, but should be taken with a grain of salt. In this case, I find its definition markedly inferior to the two others I've quoted, but it does give an indication about how the man on the street might define the idiom:
When You or Someone You Know Pisses off the BIGGEST Biker In a Bar and Is About to get his ASS FULLY Killed
By the way, when I tried this exercise with push the limit, I wasn't so lucky. OneLook does provide several results for push the envelope (which is a similar phrase), but none for push the limit.
If you ever find yourself in that situation, though, ELL is a great place to get additional help. However, you'll find that your questions on ELL will be much more enthusiastically answered and upvoted if you include your research. In other words, there's a right way to ask, and a wrong way to ask. The wrong way simply asks what a phrase means; it includes no prior research, and provides no indication of the context where you've encountered the phrase.
Here is the WRONG way to ask:
What does ‘push the limit’ mean?
Sometimes I see the phrase push the limit, but I don't know what that means. Can anyone explain the meaning of that phrase?
That question doesn't indicate any prior research – it doesn't tell us where you found the phrase, what you already know, or where you looked for help.
Here is the RIGHT way to ask:
What does ‘push the limit’ mean?
Sometimes I see the phrase push the limit, but I don't know what that means. For example, in a review of a television show, I saw:
"Shameless" always knows how to push the limit and make 100 different things happen in one episode.
I tried looking up the phrase push the limit on OneLook, but it returned no matches from the dictionaries. I also tried looking up the phrase on Google, but all of the examples just use the phrase – I couldn't find anything that explained its meaning.
Can anyone explain the meaning of the phrase push the limit?
The context might be very important, because sometimes words or phrases can mean very different things in different contexts. (If Mary Elizabeth Braddon had written about a "gay marriage" in the late 1800's, for example, she might be referring to something quite different from what that phrase generally means today.) The prior research is quite helpful, too. By telling us you couldn't find the phrase in OutLook, I won't bother looking there. The community also won't resent how it feels like we are doing legwork that you should have done, and that will spare you from a comment saying as much – perhaps with an accompanying close vote or downvote.
However, ask your future questions as admirably you did asking this question, I'm sure you'll do fine. This was an excellent question, and I hope the answers you get here prove to be helpful.