When a machine needs a little maintenance, my employer takes me off the clock (time out) until the problem is resolve. I am at the job for 12 hours and if a problem arrises within that 12 hours I would only get paid for 10. Yet I am still at the job site. I am allowed to leave but I must be there once the problem is fixed. How would I know the problem is ressolved. Is there such thing as timeout??

Dear Sirs/mam

It's fair for you to understand the parameters and working constraints of the job before you take the job. If your job is to run a machine and that machine is offline, it is reasonable to end your shift early, or take these "time outs" as you've explained.

This isn't about "fair", that thinking will get you a world of difficulty, this is about "agreement". The job only pays when there is:
a) work to be done
b) a machine available to do it on

If that is acceptable to you, then keep the job and use it to your advantage as best you can.

If it is not acceptable to you, then you do not have to do that job. Begin to seek another and take it once you locate it. Do not quit your current job until after you've secured your new job.

There really isn't a third option, the one you're trying to create, where you make them pay you for work you aren't doing.

Again, it may not be "fair" that you don't get paid when the machine is down, but it is the job, and it sounds like you understand that already. Accept it, or don't, but don't be a problem employee, or they will exercise a 4th option... replacing you without your permission.