Might be dumb question: loosening spark plug

[Rick L]

OK. This might be a dumb question but how much force can you apply to loosen the spark plug? I have two spark plugs that will loosen about half turn but after that they get stuck. I didn't apply too much force in fear of creating major problem like breaking or stripped something. Other four spark plugs came out pretty easily. I do have a torque wrench so I can set it before loosing so I don't over force the plugs... Any idea? By the way, my car is 1995 525i M50. Thanks in advance for any info...

[whiskychaser]

After half a turn they should be pretty free. If it was mine I'd use a drop of penetrating oil and work the plug in and out to free it. Clearly you dont want risk cutting new threads in the head. I'd suggest you use a 3/8" ratchet but grab it with one hand directly over the plug and not at the end of the bar. That way it limits the amount of force you can apply and is actually how I tighten plugs

[h2oyo]

I agree with whiskychaser, I wouldn't want to hurt the head. I have always felt that about 1 full turn or as the crush washer pressure is relieved it turns out with fingers. I would use a little penetrating oil and work it back and forth a little and see if it will come out nicely. If it does I would put a dab of anti-seize on them all to help make sure this doesn't happen again in the future.

[632 Regal]

never EVER remove plugs when hot in an aluminum head, it will gall the threads EVERY time.

You are very lucky!