If you do a lot of ATV work, you can't beat these ultrasonic cleaners. We just purchased a new 10L one as well, as our older 2-gallon one just burnt up. This makes our 4th one, but we can't live without one!
You probably should NOT use any kind of flammable solvent with these, as we have seen all kinds of things go wrong with them. If the solvent gets too low, you can get hot spots on the tank from the heater, not to mention the electrical aspect of these. Usually the circuit boards burn up, and then they are toast.
We use a biodegradable cleaner called "Awesome", available locally from Family Dollar for $3.00 for approx. 2 quart jug. We mix it 50/50 with water, and carbs come out looking brand new!! I would caution putting the vacuum slide and diaphragm in with heat. I don't think the soapy cleaner hurts them any, but we just spray them with Awesome, in the sink, scrub 'em clean, and give it a good rinse. Haven't had any issues with rubber o-rings, plastics, or anything else in the utrasonic cleaner. We usually let carbs sit overnight with the heat on after cleaning (temp turned down some), and by morning, they are ready to be rinsed, dried, and put back together. I would guess that we have done well over 100 of them.