Marvel Mystery Oil is an excellant penetrating oil as well as a fuel and oil additive. You can put Marvel Mystery Oil on the rusty bolts and leave set for 24 hours. The easiest way is to put Marvel Mystery Oil in a spray bottle and spray the rusty bolts. You may want to repeat this step several times.
The other product you may want to try is Marvel Super Lubricant in an aerosol can. This product also is an excellant penetrant, but it is slightly thicker and will cling to the rusty part a little longer than just the Marvel Mystery Oil. Leave this product set for 24 hours and repeat if necessary.
