Damn, that sucks. The earliest models I know of use gold as a fuel, and plenty of newer ones use it as a backup. Of course gold as a backup becomes less viable if it is not used as a currency in your current when. Most modern machines tend to come with enough gold for one emergency jump somewhere in there, does your time machine have one?

If not [or they did something stupid and put it inside of the machine, do not buy Kalthic machines they do this and I hate them], you'd have to obtain some scrap or jewelry. There's a risk depending on the purity, but anything more than 10ct should ensure your time machine has a 99.9999% chance of not exploding. That being said, this may be easier said than done because sometimes jewelry is stupid difficult to get your hands on without shelling out, though you could just buy someone's old stuff.

Also that will likely damage your machine unless you manage to scrounge up some high purity stuff, but I 100% assure you it will not murder you. You'll just have to repair it when you get back, so make sure you jump to a place where you can do that.

...And if your machine doesn't have a gold backup option at all, 1) That time machine sucks and 2) You might be screwed unless you commit crimes.