Spark Plugs stuck - Mercruiser 3.0L Alpha One

[dean_cox]

Good Evening everyone and happy Easter.

I wanted to change the spark plugs today on my 1997 Maxum with a Mercruiser 3.0 Alpha One engine. I have a spark plug remover tool, and put a lot of pressure on trying to unscrew the plug, but no luck. I guess I could have turned harder, but was concerned about stripping the thread and then getting the plug stuck.

I was going to spray some WD-40 on the plugs and leave them for a bit to see if that helps? I thought I would check here with the experts first before doing anyting else.

Please let me know if you have had this issue before or any recommendations. There looks like there is corrosion on the nut on the plug.

All help is appreciated!

Thanks,

Dean

[mmwjr]

Dean use some PD Blaster and warm the engine up then try again.

[jrsick]

Yep, PB Blaster and warm engine should help. You may also want to try and tighten the plug slightly to break the rust bond.
Be sure to vacuum the spark plug tunnel before removing the plug to get out any debris and rust before removing the plug.
The plug is going to be tight when you put the new one in. Count the number of turns required to remove the plug and get close to that number when installing new plug.
Don't use anti-seize on the new plug; the anti-seize will make turning the plug even more difficult. A light coat of oil will help.