140 is WAY too hot. Unplug that UTH now and don't plug it back in until you have the thermostat hooked up to it. Since you have a bulb as well, he shouldn't get dangerously cold until you can get a thermostat. The lamp should be regulated too, but they're more likely to get burned on a UTH so that's the more immediate concern. Those temps are in the range that you're just lucky he hasn't burned himself yet, so fixing that ASAP will save you a vet bill.