[DAVES7DNOVA]

I bought a gallon of EVAPO-RUST from Harbor Freight. It is good for small parts because the part has to soak in it. I leave them in the solution for a day or two, or until the rust is gone. I think it is great for nuts and bolts that you want to re-use. It is about $20 a gallon.

 

[65Nova4door]

looks good.

the same company makes a product that you can run through your cooling system.

 

[itslow]

I've found it does work well on smaller parts with a little surface rust; haven't tried it with any sort of heavily rusted parts, though.