Spark Plugs... stuck?

WDWBen

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So, I've decided to get a bit more handy with my car, and save some money by replacing my own spark plugs. I've never done this before. I attempted it on Saturday, but stopped because I got nervous I was going to break something, and my Miata is a daily driver.

Background: 2012 Mazda MX-5 2.0L, 60,000 miles. Used a hand-ratchet with a socket extension and a 19mm magnetized spark-plug socket to attempt to remove the plug after successfully removing the coil pack off the top. I'm having a lot of trouble removing the plug (I started with the plug closest to the windshield, as it was farthest away and I thought it would be the hardest to work on because of a lack of leverage. I know I'm not the strongest guy on the planet, but I just couldn't get the plug to budge more than a (highly technical term) smidge. It feels like if I keep working it, I'm going to break something, so I stopped, reversed the 8th turn of the plug back in, and buttoned everything up. I have a number of questions.

1) Should I be using a bigger (read longer handled) ratchet?
2) Should I be using a torque wrench instead? If so, what size? I don't imagine that I should use the same kind I would use on lug nuts.
3) Should I be using PB Blaster or WD-40 before trying to undo the spark plugs?
4) [insert other questions I should be asking but don't know enough to actually ask]
 

bone

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what direction were you turning? :p
 

WDWBen

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Wow, so very funny... and not at all useful to the question I asked. If I removed the 10mm bolt holding the coil packs on, rest assured that my ratchet was set to the right direction to move bolts.
 

Spectre

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That's not unusual if the plugs have been in there for a while. Bimetallic corrosion is a heck of a thing. You should try using a longer handled ratchet, flex handle, or breaker/cheater bar to try to get them out. Or use an electric impact.

Before removing the plug, vacuum the spark plug well out to remove any potential debris (or use compressed air to blow it out). When you remove the plug, examine it to make sure the spark plug threads in the head didn't come out with it. When putting new plugs in, use the appropriate anti-seize to prevent this problem from happening in future.
 
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WDWBen

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Spectre;n3546794 said:
That's not unusual if the plugs have been in there for a while. Bimetallic corrosion is a heck of a thing. You should try using a longer handled ratchet, flex handle, or breaker/cheater bar to try to get them out. Or use an electric impact.

Before removing the plug, vacuum the spark plug well out to remove any potential debris (or use compressed air to blow it out). When you remove the plug, examine it to make sure the spark plug threads in the head didn't come out with it. When putting new plugs in, use the appropriate anti-seize to prevent this problem from happening in future.
Question about anti-seize: everybody on the Miata forums says not to use it because it's an aluminum block, and that modern spark plugs come with it already on the threads. They also say that anti-seize would throw off your torque values (not that I'm using a torque wrench to install the plugs, I was going to ratchet them in until "good-and-tight."). Should I use it anyway? I did a ton of Googling on it before attempting everything on Saturday, and that's the conclusion I came to, but I'm open to being wrong.
 

Spectre

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Most spark plugs don't actually come with anti-seize compound on them. They sometimes come with anticorrosive plating, but not always. Double check to see what your specific plug has. http://www.jagrepair.com/images/AutoRepairPhotos/NGK_TB-0630111antisieze.pdf

That said, if you're running into problems with plugs seizing in your head, you may want to use a high temp antiseize anyway. Ford has specified that antiseize should be used on all 2V and 3V Modular V8s due to spark plug thread stripping. An old mechanics' trick was to put a drop of oil on the plug threads prior to install to hopefully prevent galvanic corrosion binding them in the head.

Also, either use a torque wrench to install the plugs or follow the maker's instructions - the Champions we put in Der Stig's XJR say to hand-tighten until snug then turn just one half turn after. The "German torque spec" can lead to stripped threads in the head.
 

WDWBen

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Now that I’m finally getting the required tools together (bought a torque wrench that reads in inch-pounds so I can torque the plugs properly, the only anti-seize I see with a temperature rating is copper-based. I assume that’s what I want, rather than aluminum-based.

Later this week, I’ll grab a breaker bar and any adaptors I need, perhaps a longer extension as well, at Lowe’s. The anti-seize I’m getting from Amazon since I don’t like the stuff in a tube that Lowe’s has.
 

93Flareside

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I’ve used copper stuff on screws that is holding down inconel if that means anything. Should be enough for the spark plugs.
 

WDWBen

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I ended up doing a lot of reading and someone said get the aluminum stuff because it also has high enough temperature ratings. I've got everything I need to do the work tomorrow; we'll see how it goes!
 
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