I am trying to change my plugs but one is pretty stuck and is not budging. Can I spray WD40 in their to try and break it loose?
Or any other tricks to get it loose? Thanks!

I belive its PB Blaster spray it on let sit ,then heat engine and spray again let sit ,it'll come loose:thumbsup:

:iagree:

WD40 is not a very good lubricant and is not a penetrating oil. It was developed to displace water in electrical connections, etc. If you want to free something, use a product designed to free stuck parts. Kroil is very good at freeing stuck or rusted parts. That is what it is designed to do. It is recommended by the members of the Model T Forum. They know rust.

Do not force it!!!

Hopefully it's stuck and not cross-threaded. That would really suck

Have you heard the saying "If it ain't broke dont F--K with it". I will bet you the car WAS running pretty good and now you wish you had left it alone. I learned this the hard way, I tried to wake my wife up the other night. (did I just say that) lmfao:catfight::postwhore::hump:

I belive its PB Blaster spray it on let sit ,then heat engine and spray again let sit ,it'll come loose:thumbsup:
Sounds like good advice!

Have you heard the saying "If it ain't broke dont F--K with it". I will bet you the car WAS running pretty good and now you wish you had left it alone. I learned this the hard way, I tried to wake my wife up the other night. (did I just say that) lmfao:catfight::postwhore::hump:

:rofl::rofl::rockon6rk:

Engine should be at room temp when changing plugs and the torque is 11 ft lbs.

To remove a stuck plug I would use a torque wrench at room temp and not go over 20 lbs otherwise you could strip the threads.........if it does not come out that way then I would try the soaking technique.............liquid wrench, pb blaster, etc

don t try to remove with engine hot

don t try to remove with engine hot

Why not, if you don't mind me asking?

Why not, if you don't mind me asking?

If you did successfully remove the plug from a hot engine the cold outside air might damage the cylinder wall or the top of the piston.

If you did successfully remove the plug from a hot engine the cold outside air might damage the cylinder wall or the top of the piston.

hmm. Didn't know that, thanks jgillen!

If you did successfully remove the plug from a hot engine the cold outside air might damage the cylinder wall or the top of the piston.that is one of the dumbest things I've ever heard :rofl:

the sad part is you might even believe it.

Well, the real reason is because Chevrolet says to take them out when the engine is at room temp. That is probably because the steel plugs expand more than the aluminum heads when hot and therefore are tighter on a hot engine.......

Why not, if you don't mind me asking?
GM says not to because the two different metals expand at different rates, if you try removing a stuck plug when engine is hot, you ll most likely break it of or strip it out

that is one of the dumbest things I've ever heard :rofl:

the sad part is you might even believe it.

let us know how that works for you and buy that poor sucker a new engine when he ruins it!

let us know how that works for you and buy that poor sucker a new engine when he ruins it!

see , you really do believe it :crazy::smack:

It's always better to be safe than sorry. IMO I'm forever cautious. :thumbsup:

It's always better to be safe than sorry. IMO I'm forever cautious. :thumbsup:

YOU MUST BE KIDDING TOO......
If you think you would warp anything by pulling the plug....well.....:abduct:

GM says not to because the two different metals expand at different rates, if you try removing a stuck plug when engine is hot, you ll most likely break it of or strip it out
You might strip the threads if there is a prior problem but I've done it literally a thousand times w/o any issues:DeadHorse:

Why not, if you don't mind me asking?


You never remove a hot spark plug from a hot engine because the head's aluminum threads can more easily gall and stick to the spark plug's steel threads. Warm is okay but never HOT.

You never remove a hot spark plug from a hot engine because the head's aluminum threads can more easily gall and stick to the spark plug's steel threads. Warm is okay but never HOT.

jeez , I've done it hundreds if not thousands of times w/o any issue

I have never heard of that happening either.:wheelchair:

Learn something every day.:coffeetime:

I have never heard of that happening either.:wheelchair: :toocrazy:

and you NEVER will

It only takes once and if you think it can not happen you are not a smart man and do not have much mechanical experience. I have personally seen stripped threads on many aluminum head engines.

http://forums.corvetteforum.com/engine-mods/1631711-spark-plug-hole-stripped-out-what-to-do.html

One more comment before i bow out of this discussion. It just doesn't make sense to change them while the engine is hot. I've been changing spark plugs in cars and boats since 1962. Always have let the engine cool, too old to change now.

It only takes once and if you think it can not happen you are not a smart man and do not have much mechanical experience. I have personally seen stripped threads on many aluminum head engines.

http://forums.corvetteforum.com/engine-mods/1631711-spark-plug-hole-stripped-out-what-to-do.html
I agree , two different metals , not worth the risk, let the motor cool down this is what the GM service manual says "Allow engine to cool down before attempting to remove spark plugs. Attempting to remove from hot engine may cause the plug threads to seize, causing damage to the cylinder head threads." But they probably don t know much, they only designed the darn thing!

Well this is enough to change my thoughts, I'll wait for cool down before changing. Definitely better safe than sorry for only a few extra minutes during cool down.:cheers:

One more comment before i bow out of this discussion. It just doesn't make sense to change them while the engine is hot. I've been changing spark plugs in cars and boats since 1962. Always have let the engine cool, too old to change now.

obviously you never raced
we do it all the time

I agree , two different metals , not worth the risk, let the motor cool down this is what the GM service manual says "Allow engine to cool down before attempting to remove spark plugs. Attempting to remove from hot engine may cause the plug threads to seize, causing damage to the cylinder head threads." But they probably don t know much, they only designed the darn thing!

you can ruin threads if you are a hammer mechanic.

we do it every weekend at the track :doh:
not one stripped thread in over 30 years , 90% all aluminum motors

obviously you never raced
we do it all the time

Actually i beat the living daylights out of a Mustang just this afternoon. Guess I'll stick with the plugs I have.

The plugs have probably been in for awhile so go easy, want to have some fun with Simple physics. Get an aluminum head ( a lawn mower one will work) measure the diameter of the spark plug hole then heat it in an oven to 400 degrees, measure it again see the difference. you can heat up the plug and do the measurements on that also. the plug gets larger in diameter and the hole gets smaller Seeing is believing!

One more comment before i bow out of this discussion. It just doesn't make sense to change them while the engine is hot. I've been changing spark plugs in cars and boats since 1962. Always have let the engine cool, too old to change now.

GM says not to because the two different metals expand at different rates, if you try removing a stuck plug when engine is hot, you ll most likely break it of or strip it out

It's always better to be safe than sorry. IMO I'm forever cautious. :thumbsup:

I agree working on an engine that won't burn your a$$! Makes much more sense to to let it cool. What Fishslayer said makes sense to me too! These different types of metals change when heat is added to the mix. On top of that Raydawg has said it the best out of every!:rockon6rk:

you can ruin threads if you are a hammer mechanic.

we do it every weekend at the track :doh:
not one stripped thread in over 30 years , 90% all aluminum motors
if you are changing the plugs 4-5 times in an afternoon to get best ET s you might not have a problem, but leave that plug in an aluminum head for 80,000 miles and see what happens removing hot. ITS JUST NOT WORTH THE RISK! let it cool .whats the rush?

if you are changing the plugs 4-5 times in an afternoon to get best ET s you might not have a problem, but leave that plug in an aluminum head for 80,000 miles and see what happens removing hot. ITS JUST NOT WORTH THE RISK! let it cool .whats the rush?

Thanks for making the distinction, two very different situations.

if you are changing the plugs 4-5 times in an afternoon to get best ET s you might not have a problem, but leave that plug in an aluminum head for 80,000 miles and see what happens removing hot. ITS JUST NOT WORTH THE RISK! let it cool .whats the rush?I'm glad I don't wait 80k between changes on my vettes plugs

drag racing :doh:

we do plug checks for circle track

did the OP ever get his lug out ? :wtf:

if you are changing the plugs 4-5 times in an afternoon to get best ET s you might not have a problem, but leave that plug in an aluminum head for 80,000 miles and see what happens removing hot. ITS JUST NOT WORTH THE RISK! let it cool .whats the rush?
I agress with you on this .Oh by they way I had a 99 chevy that had 230,000 on it & never changed the plugs & it was still running great when I traded it off .And did pull one plug at 200,000 after it cool down it was a little tight but it came out & looked good to me .........:patriot:

jeez , I've done it hundreds if not thousands of times w/o any issue


The only reason you got away with it was because the aluminum head had cooled considerably before you removed the plugs. Had the head been up to full operating temperature, you almost certainly would have stripped one or more. Like I said in my post, warm is okay but never hot!

I am trying to change my plugs but one is pretty stuck and is not budging. Can I spray WD40 in their to try and break it loose?
Or any other tricks to get it loose? Thanks!


So did you ever get it out without any damage?

I'm glad I don't wait 80k between changes on my vettes plugs

drag racing :doh:

we do plug checks for circle track

did the OP ever get his lug out ? :wtf:
Most auto manufacturers recomend changing spark plugs at 100,000 miles.I ve seen lots of engines with alot more than that on them ,still running fine. But don t try removing hot!

Most auto manufacturers recomend changing spark plugs at 100,000 miles.I ve seen lots of engines with alot more than that on them ,still running fine. But don t try removing hot!

I'll agree with that statement.:thumbsup:

The only reason you got away with it was because the aluminum head had cooled considerably before you removed the plugs. Had the head been up to full operating temperature, you almost certainly would have stripped one or more. Like I said in my post, warm is okay but never hot!

wrong , we pull right after we chop the throttle, max of 5 minutes after

wrong , we pull right after we chop the throttle, max of 5 minutes after


I think you're getting away with it only because hard carbon hasn't had the chance to fill up the threads between the plug and the head. So you're working with clean components whereas the components aren't clean in a street driven car with maybe 80-90,000 miles on it.

I had a plug stuck in my old 6cyl nova once and I tried taking it out when the engine was warm and it broke in half! I am sure there were a handful of other variables in play then just the engine being warm though.

Careful, breaking a plug off while still inside is very bad!!

I had a plug stuck in my old 6cyl nova once and I tried taking it out when the engine was warm and it broke in half! I am sure there were a handful of other variables in play then just the engine being warm though.

Exactly

I had a plug stuck in my old 6cyl nova once and I tried taking it out when the engine was warm and it broke in half! I am sure there were a handful of other variables in play then just the engine being warm though.
The biggest variable on a Corvette engine is the HEAD IS ALUMINUM and the PLUG IS NOT! You only need break or strip one plug to know you should have let it COOL!

The biggest variable on a Corvette engine is the HEAD IS ALUMINUM and the PLUG IS NOT! You only need break or strip one plug to know you should have let it COOL!

Absolutely! You do that in an aluminum head and you will have a rude awakening!