changing spark plugs that are tight

[steb23]

I need to change the spark plugs on my 172 but they seem to be really tight and dont seem to want to move, what is the best way to remove them as I don’t want them to snap. Is it best to have the engine warm or cold?
Steve

 

[caister]

You shouldnt snap them. Use a socket set if possible to get more turning force. Probably best to do it while the engine is cold.

 

[sideways danny]

a little penetrating oil and a few turns back and forth rather than straight out in one go should help loosen the threads up a bit