SEIZED SPARK PLUG

I PURCHASED AN ENGINE USED WITH A-460 HEADS, AND WAS DISASSEMBLING TO INSPECT PIECES AND
REPLACE BEARINGS AND RINGS. THE PURCHASE CAME WITH ANOTHER SET OF A-460 HEADS WHICH IM
INSTALLING. WHILE REMOVING THE SPARK PLUGS, I FOUND THAT QNE WAS SEIZED. I TRIED SPRAYING
THE UNDERSIDE WITH THE HEAD REMOVED BUT THE PLUG STRIPPED COMING OUT. MY QUESTION IS WHAT
ARE THE CHOICES ON FIXING THE HEAD? IS A HELI-COIL MY ONLY OPTION?

An insert is the cheapest solution.

I would not suggest a helicoil. There are thread inserts that are a much better option, instead of a strand of wire, the hole is drilled and oversized so a steel sleave is inserted with a shoulder so it cranks down tight. Ultra ubber thread locker is also used to ensure it stays locked in place. Now you have a steel thread for the spark plug hole(s).

Don't know why most high end heads don't come with all holes done that way anyhow.

Have a machine shop do one or all, some of the inserts are called timecerts, but various manufactures supply them in assorted sizes.

time cert, just had to do one on my sbf head.

I agree that all Alum heads need these.

...And always use a dab of anti-seize compound before you screw anything into aluminum.

THANKS TO ALL FOR THE REPLIES, THE HEADS WILL ONLY BE USED FOR SPARES AND I DIDNT WANT TO
THINK ABOUT USING THEM FOR BOOKENDS . DO YOU THINK THE INSERT WILL HOLD UP TO THE CYL.
PREASURES OF 15 TO 1 COMP.?

Yep.

mustang557 wrote:THANKS TO ALL FOR THE REPLIES, THE HEADS WILL ONLY BE USED FOR SPARES AND I DIDNT WANT TO
THINK ABOUT USING THEM FOR BOOKENDS . DO YOU THINK THE INSERT WILL HOLD UP TO THE CYL.
PREASURES OF 15 TO 1 COMP.?

No problem.

used them on a procharger car making 42lbs of boost without issues