The naptha in the JP
-4 is very bad for the insides of the HMU in the -7.
If it wasn't for that the engine really wouldn't care what went through it as long as it wasn't explosive and would burn smoothly.
All of the fuels mentioned are kerosene or diesel type fuels while JP
-4 is Naptha based and Jet B is also a high volatility fuel.
One may educate the ignorance from the unknowing but stupid is forever. Boswell; ca: 1533