I think all the washer tubs with pumps warn about no flammable fluids. Water based grease removers work almost as well but I go with varsol/paint thinner/kerosene, us old timers get stuck in our ways. These aren't super volatile, but it is a fire risk. Probably the warning is for legal reasons - some moron might use gasoline which would be extremely dangerous.
Solvents will destroy the pump that Harobo Freight (Princess Auto here in Canada) cleaners use. It's good for a few months but after that - kaput.
Finding a hose for a dispensing brush that doesn't turn to stone in solvent is tough as well. haven't managed that yet, I use vinyl which goes hard in a week or so. Cheap, though.
I replaced the original dead pump with a Little Giant one which hasn't been ruined by varsol in 3 years.