For some time before eating, put on the bolt soaked in kerosene on a rag. The more the cloth will lie down on it, the better. If no time, then you can use the same kerosene or legkopodwijnaya lubricant WD-40. Knock the bolt with a hammer, then put a kerosene or WD-40. Wait for 1 minute, and five knock bolt. You can then try to Unscrew. Is that any grease or kerosene on hand, then you can use brake fluid or regular vinegar.
You can also try to "shake" the bolt. Start to loosen and tighten. If the bolt has moved a little, start again to Unscrew. As soon as the bolt stops spinning, start to wrap it all the way. Thus, slowly and not nervous, you Unscrew a rusty bolt.
If the bolt can not be loosening any of the above methods, take a hammer and chisel. Put the chisel on the edge of the cap boltand at an angle. The sting of the chisel should be directed in the direction of loosening the bolt. Apply sharp strong hammer blows on the chisel. Thus, you can loosen virtually any rusty bolt. You can also Bang on the key, but not much. If the bolt can not be, the key is easy to lick their faces the bolt.
Very effective way is to heat the bolt. It is possible to heat a soldering iron, blowtorch, burner and boiling water. It is necessary to heat strongly. The more you heat, the higher the chances that you can easily Unscrew a rusty bolt. The main thing is not let it cool, twist the bolt until it is hot.
Do not lubricate the bolts when tightening the grease and petroleum jelly. These greases are designed for rubbing parts. If they lubricate the bolt or nut, over time the grease will zacatepec and screw will be harder than a rusty bolt.
Don't forget to lubricate the bolts and nuts when they spin, graphite. It can be bought in any shop.