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Releasing seized nuts and bolts by heat

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What is the issue?
Bolts and nuts, like most every fastening, have a tendency to seize up on boats due to the challenging sea going environment.

Why address this?
A seized screw, bolt or nut can halt a project, cause frustration and cost money.

How to address this?
Use a gas torch to apply heat to the bolt or nut as presented in figure 1.
Heat the bolt and surrounding metal with butane gas torch. Butane, however, burns cool and for large bolts in an engine block you may need to go for a propane torch found in most workshops.
The objective is to bring the part up to a dull red colour. Once this happens the molecular bond fixing the bolt or screw threads should break. The heating and cooling action fractionally expands the metals at different rates helping to break the metals apart. After it has cooled down the bolt or nut should un-turn.
Don’t apply too much heat as it can cause the fastener to soften its temper and perhaps break off. If you are heating in an area that has fibreglass or wood nearby place a quantity of protective wet rags around them so that the heat is dissipated and does not cause any damage - see figure 2 for example removing keel bolts.

With thanks to:
Michael Harpur, Yacht Obsession.

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