Hi Joe:
The use of heat to loosen seized nuts or bolts depends on the expansion of
the metal. The bolt expands which breaks the bond between its threads and
the threads into which it is turned. This system will not work effectively
in the case of an aluminum/steel interface because the aluminum conducts
the heat away too rapidly for the interface area to become hot enough. If
it were to become hot enough, there is a good chance that the aluminum
might melt before the steel got to a red heat - which is needed to cause
the required expansion.
The second problem is that the bond between the two parts is probably
electrochemical as a result of failing to use anti-seize compound where two
dissimilar metals are involved. The only safe way to remove the offending
bolt if it will not unscrew is to drill it out. Even this may result in
the need to re-tap the hole. The best way to get a firm grip on the bolt
is to do as others have suggested and weld a nut to it. There isn't much
worry about damaging the case if the welding process is not prolonged and
if care is taken to assure that the welding flame (if using oxyacetylene)
is not playing on the surface of the casting.
John
>Will,
>I can't fathom how heat will do more than make the thing seize tighter.
>Heat expands. Now if you heat the case, maybe that would work. Maybe
>if you try "Dry Ice" and contract the plug, it would free it. ---Just a
>thought---
>
>Joe Curry
>
>Will O'Brien wrote:
>
>> It's simple.
>> HEAT.
>> Use a torch on the thing, heat it up.
>> Then use your vice grips, etc.
>> If that doesn't work...
>> More HEAT.
>> It will work.
>>
>> Will
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