[JoeShmo]

Before anyone says anything: yes. I used Google to search for threads on this topic and came up with only a couple, some of which helped me. Anyways, here goes.

I'm very new to car maintenance. That being said, spark plugs should be an easy install, no? It went very smoothly until I got to the far right cylinder (when facing engine bay from front of car). I've got Cobbs intake, so that far right spark plug is only accessible by unbolting and pushing the intake tube back to twist out the coil. After unscrewing the stock spark plug, I coated the new one in anti-seize, then tried to install it. But the spark plug would not sit in the threads straight. Let me break down the process I went through:

1. Put new plug in about 1/3 of the way. Very hard to turn, so backed it out.

2. Tried a different plug just to be sure it wasn't the threads on the previous plug. Same result.

3. Tried to put the plug in again, keeping it as straight as possible. (This is where my inexperience got the best of me). Started torquing plug harder than I should have, heard what I now believe was the porcelain cracking. Backed plug out, inspected for damage, found nothing.

4. Tried to install same plug again, keeping it as straight as possible. Figured it was just hard to turn (again, inexperience got the best of me). Torqued so much that porcelain ended up breaking off of the top, and is now sitting on the edges of the spark plug and the hole (with the hole still plugged). As far as I know, nothing went into the cylinder. I, of course, will check to be sure if I'm able to get the plug out after I get the pieces out.

My question: Do any of you believe the spark plug hole is cross threaded for that cylinder? Or does it just require a bit more finesse than the others? NONE of the new plugs would go in straight, meaning I would have cross threaded it when pulling out the stock plug, which I find hard to believe.

I've read about retapping the hole for new threads, but will not be attempting that. I barely trusted myself to do spark plugs, and you can all see how that turned out. If it's cross threaded, to the shop it goes (ugh).

 

[JoshCrane1]

Sounds like a shop visit is in order, make them worry about it (and they are responsible if they decide to accept the job). Bad luck indeed.

 

[STGeorge]

That´s a bad thing... Not that I´m really an expert in what to do now, but here´s what I think: What makes me wonder is how you could break the spark plug like that. When trying to turn in a screw with a ratchet always hold it with one hand as straight as possible right in the center of the screw, avoid to put much force on it in an angle. You will damage the head of the screw, or in your case the spark plug. Also, whenever you need more force to do something than you expect, trust your senses, something is wrong!!! I learned this lesson by just saying to myself "aah, will work anyway" too often. No it won´t! In 90% I broke something already or made it worse (and THEN broke it).

That the hole is closed is kind of a lucky situation, it gives you the chance to get the broken parts out. I would try it with an vacuum cleaner maybe. But, to be honest, I really think you damaged the thread at least a bit, some small metal pieces might have found the way inside. I would suggest to bring it to the shop because you will not be able to take the head down and rework the thread and clean everything out. Killing the engine by changing spark plugs is nothing to be proud of, but happens. I did this myself to my first car. Something fell inside... a short startup... piston, head and cylinder went to Walhalla in seconds.

When doing it again (if...) try to turn the spark plug only with fingers instead of a ratchet, you should be able to get it in at least for a few turns. You will notice if it´s not straight and feel if there´s too much resistance. Also the use of anti-seize is not recommended and not needed for spark plugs (according to Denso). If you put them in with the right torque you won´t have problems to get them out later.

 

[lolubeenpwned]

I have the same issue with that plug on mine, CP-E Alpha intake goes right over it.

Good luck man. Should have gone with your gut when it didn't seem right and waited, or pulled the intake to accommodate. Let us know how it unfolds.

 

[JoeShmo]

Thanks guys. I'm going to have it towed to the Ford dealer so they can take a look. Called a couple shops around my apartment and they are very hesitant to attempt anything. This is the first car I've owned myself, so this will be one expensive lesson that I had to learn the hard way. Oh well, life goes on.

Really really hope they don't decide the head needs to be pulled to clean out the cylinder. Hoping they have a powerful enough vacuum to get out the small metal pieces that may have fallen in from cross-threading.

 

[Hosz]

Were you using a spark plug socket or an ordinary deep well socket? I had the porcelain break on me before using an ordinary socket. I suspect the socket was not deep enough and the pressure from tightening it down broke the porcelain. Fortunately it was only the porcelain that broke and I could still get the plug out because the metal nut was intact. I would check to see if I can still get a socket on the nut to get the plug out then get a new plug and see if it can be hand threaded in. Once tight, torque it down to spec. If you can get it started by hand threading, you may be okay. If it cannot be hand threaded, you probably cross-threaded it and will need a heli-coil. I would not do this on a head if you never did a heli-coil before. Too big a risk of something dropping into the cylinder and making your life even more miserable.

In case you did not know this, when changing spark plugs, you should always start by hand threading. This is especially important on cars with aluminum heads.

You should also get a spark plug socket. Spark plug sockets have rubber inserts that hold the spark plug in place that make it easier to install and remove. If you do not have a spark plug socket or the spark plug is at a weird angle, you can use a rubber hose. Stick the plug on the end of the rubber hose and turn the rubber hose.

You should also get a torque wrench unless your hand is already a finely calibrated torquing device. Spark plugs are usually tightened to around 15 ft.-lbs. but check the actual specs in case they are different for an ST. When touching anything on the head you don't want to mess around with torque specs. You should also let an engine cool before changing spark plugs, aluminum engines in particular. The metal is softer when hot and more prone to cross-threading.

Also, some spark plugs, like NGK, don't require any anti-seize and NGK recommends against using it.

Don't beat yourself over this. Everyone who works on their ride was in or will be in your shoes at some point. Don't let it discourage you from working on your ST. No one will ever spend the same amount of time and attention to detail working on YOUR car as YOU will.

 

[JoeShmo]

I have the same issue with that plug on mine, CP-E Alpha intake goes right over it.

Good luck man. Should have gone with your gut when it didn't seem right and waited, or pulled the intake to accommodate. Let us know how it unfolds.

I was able to move the intake enough to get in there and work. Just was odd that no other spark plug would fit into the threads on that particular cylinder immediately after I removed the stock plug. I just find it hard to believe that it would cross-thread that easily, but I know that aluminum is very soft and susceptible to this.

 

[JoeShmo]

Were you using a spark plug socket or an ordinary deep well socket? I had the porcelain break on me before using an ordinary socket. I suspect the socket was not deep enough and the pressure from tightening it down broke the porcelain. Fortunately it was only the porcelain that broke and I could still get the plug out because the metal nut was intact. I would check to see if I can still get a socket on the nut to get the plug out then get a new plug and see if it can be hand threaded in. Once tight, torque it down to spec. If you can get it started by hand threading, you may be okay. If it cannot be hand threaded, you probably cross-threaded it and will need a heli-coil. I would not do this on a head if you never did a heli-coil before. Too big a risk of something dropping into the cylinder and making your life even more miserable.

In case you did not know this, when changing spark plugs, you should always start by hand threading. This is especially important on cars with aluminum heads.

You should also get a spark plug socket. Spark plug sockets have rubber inserts that hold the spark plug in place that make it easier to install and remove. If you do not have a spark plug socket or the spark plug is at a weird angle, you can use a rubber hose. Stick the plug on the end of the rubber hose and turn the rubber hose.

You should also get a torque wrench unless your hand is already a finely calibrated torquing device. Spark plugs are usually tightened to around 15 ft.-lbs. but check the actual specs in case they are different for an ST. When touching anything on the head you don't want to mess around with torque specs. You should also let an engine cool before changing spark plugs, aluminum engines in particular. The metal is softer when hot and more prone to cross-threading.

Also, some spark plugs, like NGK, don't require any anti-seize and NGK recommends against using it.

Don't beat yourself over this. Everyone who works on their ride was in or will be in your shoes at some point. Don't let it discourage you from working on your ST. No one will ever spend the same amount of time and attention to detail working on YOUR car as YOU will.

Thank you. You're helping put my mind at ease. Yes, I was using a spark plug socket, I was just being a complete bone-head. I got the anti-seize idea from the CJ PonyParts install video (they were also installing the NGK spark plugs, which are the ones I used), but won't use it from now on. I was actually able to get that spark plug started with just my hand on the extension+spark plug socket, but got the ratchet once I couldn't get it in any further. Did exactly what ST George said (told myself "it'll work" and just kept cranking till SNAP). Just praying that the dealership can fix this. The last thing I need in my life is a broken motor.

 

[lolubeenpwned]

Yea, sh*t happens, all you need to do is learn from it, and next time consult us if something feels weird. It might take a day or two to get the solid answer, but planning is key. I'm not trying to be a hard ass on purpose, I've just done some very stupid stuff and wish I would have payed closer attention myself.

I once botched a cam install on a duratec. Slapped every piston, bent every intake valve. Put a new head on. Then I didn't read inch pound, so I tried to torque a head stud and broke that off, in the bottom end. Tried to drill that out and broke the water jacket.

Costed me around $3,000 to put cams in that car. And then 2 years later I pulled them out and sold the car. Never changed the pistons out. Wasn't forced induction or anything, so the hot spots weren't that terrible...maybe. lol.

You're motor will be fine. If any particles got in there, a vacuum should be able to get them out.

 

[JoeShmo]

Yea, sh*t happens, all you need to do is learn from it, and next time consult us if something feels weird. It might take a day or two to get the solid answer, but planning is key. I'm not trying to be a hard ass on purpose, I've just done some very stupid stuff and wish I would have payed closer attention myself.

I once botched a cam install on a duratec. Slapped every piston, bent every intake valve. Put a new head on. Then I didn't read inch pound, so I tried to torque a head stud and broke that off, in the bottom end. Tried to drill that out and broke the water jacket.

Costed me around $3,000 to put cams in that car. And then 2 years later I pulled them out and sold the car. Never changed the pistons out. Wasn't forced induction or anything, so the hot spots weren't that terrible...maybe. lol.

You're motor will be fine. If any particles got in there, a vacuum should be able to get them out.

No, you're not being a hard ass. Just telling it like it is (which more people need to do). My goal now is to start asking questions before creating problems for myself. Just trying to get the job done too fast and not stopping to think about what could happen if I overtorqued a spark plug.

 

[lolubeenpwned]

That's exactly how my situation happened as well. I was just trying to hustle through putting those cams in at a friends house and we tried to rush it, not paying close enough attention to detail. All you have to do now is learn from it.

 

[JoeShmo]

That's exactly how my situation happened as well. I was just trying to hustle through putting those cams in at a friends house and we tried to rush it, not paying close enough attention to detail. All you have to do now is learn from it.

Definitely. It's a recipe for disaster, trying to go too fast.

Ford had the spark plug out within about half an hour (got a call at 7:45am this morning). Found another NGK from a nearby parts store and installed it for me. Cylinder head isn't cross threaded or damaged, so we are good to go there.

Tech asked me: "Why do you want to use these spark plugs instead?"
"....I'm going for a step colder"
"Okay!"

Guess they don't care THAT much about my mods.. it's not like the intake is hiding.

 

[lolubeenpwned]

Glad to hear it was all good. Just take your time next time.

They don't care about the mods because they already know your warranty is gone. lol.

 

[brian60]

Good call going to a Ford Dealership. Don't go to a shabby place for something like this, yeah, Ford might charge you an arm and a leg for such a simple little procedure, but this simple procedure can because a really expensive one when messed up. So, you just have to own up to the mistake and have it taken care of properly.

 

[JoeShmo]

Glad to hear it was all good. Just take your time next time.

They don't care about the mods because they already know your warranty is gone. lol.

Ha! Very true. Glad they are at least not giving me grief about it.

Good call going to a Ford Dealership. Don't go to a shabby place for something like this, yeah, Ford might charge you an arm and a leg for such a simple little procedure, but this simple procedure can because a really expensive one when messed up. So, you just have to own up to the mistake and have it taken care of properly.

Yeah that was my thinking as well. I called a couple local shops and they were very hesitant about taking a look. So just went to the dealer. They probably did charge more, but at least now I've got the piece of mind knowing that everything is clean in there. They assured me they borescoped to check for debris and it was all good.

 

[carterreiss]

How much did the ford dealership charge you? I know this was over 3 years ago but the same exact thing just happened to me.

 

[Unreal]

For future use, I would recommend using a magnetic 10" long 5/8" spark plug socket. I use this (picture is linked to Amazon)...



There are plenty of other choices too of course, but I find this one works well.