I had to take the head off my car recently and havent got it back on the car yet. The question is when I was sitting and looking at what is left of the engine in my car I noticed a small bit of rust in 2 of the cylinders I wiped them down and sprayed some WD40 in them is that gonna hurt anything because I didnt have anything else at the time. Hope I can get this thing back together soon.

 

I used carb cleaner with most anything that I do with my engine work that involves cleaning, because it evaporates away and doesn't leave a film. I don't know from experience if WD-40 will cause any damage, but I DO know from experience that carb clenaer is pretty harmless.

 

Thanks I should have thought of that being that I have also cleaned alot of stuff with carb cleaner. Ill get a couple cans and try it out Im sure it will work.

 

A lot of machine shops put WD-40 on cylinder walls after a block has been cleaned and honed. I don't think WD-40 will hurt...