Can or spray gun

engine degreaser and a power washer is the hot ticket. i like to apply 3-4 light coats letting them set up 10-15 minutes between each . if you use too much paint or put it on too heavy, it likes to chip off. when i use orange, i like to dust the engine with a high temp engine flat white as a basecoat. it helps with getting great coverage with the orange topcoats