Quote:
Originally Posted by gedaggett
 NEVER NEVER EVER REMOVE ON A HOT ENGINE.
You most likely have an aluminium head which expandes with heat and will vise up on the plug. If you think a broken plug is bad try bringing the plug out only to find that it brought the head threads with it. You should never remove any bolt from a hot aluminum block or head. It be very bad. |
The hole for the spark increases in size when hot. I have no idea where you got the information it decreases, but it's wrong.