An old machinist told me this one. He told me for really rusted screws-he would soak the part overnight in either Coke Cola or Pepsi. I have heard Diet Coke would work also. I tried it a few times, but the problem I’ve with this trick is the cola would bead off if I tried to pour it on. I have to find a way to keep the fluid where I need it.
Anyway, I was tearing apart an NP205 last week when I got stalled on the front yolk. It was rust welded to the front output shaft. I put so much strain on it with a gear puller, one the ears started to break off, and the yolk still wouldn’t budge. I look at it and notice the yolk would make a perfect bowl if I lay the case on its back, so that is what I did. I went to the refrigerator and pull a half empty can of flat Diet Coke. I poured it in the yolk and went to work. The next day, I noticed the cola was gone, so it must have drained down the spines of the yolk. I took out my gear puller again, and hit it with my impact wench. The yolk didn’t come off as easily as I hoped but it came off.
Anyway, I was tearing apart an NP205 last week when I got stalled on the front yolk. It was rust welded to the front output shaft. I put so much strain on it with a gear puller, one the ears started to break off, and the yolk still wouldn’t budge. I look at it and notice the yolk would make a perfect bowl if I lay the case on its back, so that is what I did. I went to the refrigerator and pull a half empty can of flat Diet Coke. I poured it in the yolk and went to work. The next day, I noticed the cola was gone, so it must have drained down the spines of the yolk. I took out my gear puller again, and hit it with my impact wench. The yolk didn’t come off as easily as I hoped but it came off.

) he poured the coke on the rusted bolts, though I don't remember what kept the soda in place. The next day, the bolts came off.