I just got done cleaning some engine irons and had a couple questions. I soaked them in zep purple cleaner and water and then scrubbed/sprayed them off. There is still some stuff left because I just used a hose, will a pressure washer be safe to use and get the rest of the layers of junk off?



Also, after doing this inside the coolant passages it looked like rust! Why did this happen? Does it matter or are these trash now? Is it bad or is there a way to clean it off? Or is it even rust? Last time I cleaned my irons this didn't happen, that's why I ask.

it's called an iron for a reason. this is what coolant helps to avoid. they should be ok get the surface rust off and coat them with some wd40

How do I get it off those? I was trying to get scotchbrite into the passages to clean it off and that wasn't really working out, too tight. The surfaces of the irons are completely fine, just the coolant passages. So after they dry should I just spray wd40 into the passages for now and call it good? This is a long term project and these are going to be sitting for a while once I'm done cleaning and painting them, so the wd40 should protect them?



This was just weird because it didn't happen last time I cleaned the parts, so I thought I'd ask.

You could use a die grinder w/ attachment and wire wheel to buff the surface rust away in the coolant passages without removing any iron. If they are going to sit for an extended period of time I would lightly coat the irons in oil and double ziploc bag them, I suppose WD-40 would work too as long as they are kept in some sort of air tight container. Of course they will need to be cleaned again later, a head rebuliding shop or similar automotive shop should only charge a small fee to run them through thier parts washer once you are ready to assemble the engine.