ALL parts cleaning has an hourly rate. I say that after thousands of hours doing it in mechanical work.
I myself use solvent based cleaners instead of water based, the water based can work but never to the degree the solvent ones will. Safer of course, until you allow for the max effect ones that use whopping amounts of alkali and then they are worse than the solvents. Any alkali not fully rinsed clean will wreck parts if left overnight, they corrode horribly.
ALL engines use gasoline and oil and the deposits are formed of such minus the volatile component. The thing that cuts them fastest is more of the same and soaktime to let them convert the dried and cooked on deposits back into more of the same surrounding them. I use fuel but outside and no source of flame anywhere. Cheap and works great and the ethanol added to it now actually makes the parts release all oil based residues completely now where before the parts would water rinse then have an oily film on them. Not any more, a water rinse pretty much has you at a bone dry part once it dries. By soaktime I mean a short set amount, leaving parts in ethanol fuel overnight will see the fuel phase separate and then you have corroded parts the next day.
To clean parts high pressure air from a blower nozzle is just about required, no paper towels, which have no business around clean parts anyway, too much paper lint getting all over the place. The air will often remove great areas in deep corners of stacked up dirt too saving lots of toothbrush work.