Mitsubishi Repair: Stuck spark plugs, chrysler lebaron, mitsubishi engine

Question
Hi Anthony-

I have a 1982 Chrysler Lebaron with the 2.6 Mitsubishi engine and auto transmission.

I bought it earlier this year and in the middle of giving it a tune up. One spark plug came out easy, another turned real hard for 1 1/2 turns so I stopped and 2 won't budge with using a standard spark plug socket and 3/8" drive ratchet. Is there a trick to getting the plugs out of this engine? I could use a bigger wrench but I am afraid of messing up the threads. Any ideas? Is the area around the plugs cast iron or aluminum?

Thanks,
Jim

Answer
Jim,
I do not know if the Mitsu engines in such an old Chrysler were iron or aluminum heads.  Though when removing the plugs, the threat of messing up the threads is a lot less than the possibility of breaking the plug off in the cylinder head.  I'd recommend spraying some penetrating oil in the well and let it sit for an hour, then try to remove the plug again.  If it's still very tough, repeat the process of spraying, waiting, and wrenching until it comes out.
Good luck!