I have a 1979 ford ranchero. My engine is making a loud rattling/scratching sound around the belts/fan area. What is it? It gets louder or rather more frequent when I accelerate, it sounds like something needs some WD-40 or like if a metal fan was scratching the metal.
First disconnect teh fan belt and start car to eliminate noise form accessories. Then check the oil pressure, it may below an dyou have an internal problem. If pressure is good then try decarbonizer on it, follow instructions on can. Ford or gm dealers have the same stuff.