MM over voltage protection??

the mamba max is only rated for up to 12 nimh cells or between 2-3s lipo packs.
however, you can run a 4s lipo pack (14.8v) if you use a external BEC, like the dimension engineering sport BEC.

i don't know about 14 cells though, that is 16.8V, which is 2v higher than a 4s pack. but you should buy a external BEC anyway, and give it a try to see if the MM will work.
it sounds like you are getting a voltage over load warning from the esc.