spark plug threads f'ed *sad trombone noises*

[analbumcover]

hi all - recently bought a 2011 X5 w/ the N55, 80k mi. Doing preventative maintenance and successfully replaces plugs 1 through 5 (the coils got progressively more rusty as I moved towards the firewall).

Anyway, plug 6, stuck. Soaked in penetrating oil over night then I slowly walked it out and get the plug removed but the washer was still in the cylinder head...odd. Fished the washer out and then went to look at the plug I just removed and half the threads are smushed.

Here's a pic of a good used one and the one I pulled.

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Thoughts on a solution? I can get a new plug into the hole and started about 1 revolution before there's resistance.

[SlowX6M]

If at all feasible, I would try to rethread the hole. Aluminum head vs steel spark plug, the threads in the aluminum have to be damaged even more.

[JellyStyle]

Originally Posted by SlowX6M

If at all feasible, I would try to rethread the hole. Aluminum head vs steel spark plug, the threads in the aluminum have to be damaged even more.

you need to thread it but you also need to pull the shavings out to do it, otherwise you will destroy that cylinder in doing so. Some say to leave the plug out and turn it over to blow them out of the cylinder, but again, there is risk. you don't need to use the thread insert, if you think that it not beyond repair. if its weak, it will blow the plug out the head into and possibly through your hood, so again, you have to do this really carefully.. if you are unsure, see who you know that's done a rethread of a plug before or do a bunch more research online.

[SlowX6M]

Originally Posted by JellyStyle

you need to thread it but you also need to pull the shavings out to do it, otherwise you will destroy that cylinder in doing so. Some say to leave the plug out and turn it over to blow them out of the cylinder, but again, there is risk. you don't need to use the thread insert, if you think that it not beyond repair. if its weak, it will blow the plug out the head into and possibly through your hood, so again, you have to do this really carefully.. if you are unsure, see who you know that's done a rethread of a plug before or do a bunch more research online.

I don't know if aluminum shavings will necessary cause any damage to the cylinder, but of course it is necessary to try and get most of them out.

If the threads are beyond repair, then a thread insert is necessary.

[analbumcover]

I think the plugs are at an angle so standard taps may create brand new threads slightly off-angle?

I'm grabbed a back tap in 12x1.25, planning to tear down the valve cover and spark plug/injector recess so I am only a few inches from the actual head/plug hole. From there I'll use the back tap to start from inside the cylinder and hopefully straighten out the threads...

https://smile.amazon.com/gp/product/...?ie=UTF8&psc=1

Any other creative ideas? trying to avoid head removal/replacement...

side bar - did I cause this on removal or was this damage done by the prior owner?

[SlowX6M]

Originally Posted by analbumcover

I think the plugs are at an angle so standard taps may create brand new threads slightly off-angle?

I'm grabbed a back tap in 12x1.25, planning to tear down the valve cover and spark plug/injector recess so I am only a few inches from the actual head/plug hole. From there I'll use the back tap to start from inside the cylinder and hopefully straighten out the threads...

https://smile.amazon.com/gp/product/...?ie=UTF8&psc=1

Any other creative ideas? trying to avoid head removal/replacement...

side bar - did I cause this on removal or was this damage done by the prior owner?

Probably prior owner, its hard to screw up the threads when unscrewing the plug.

[analbumcover]

good news, back tap worked. I had tons of thread at the bottom of the spark plug hole for the tap to use. New plug when in by hand and I torqued it down. For anyone doing this, you have to have SOME good threads for it to work. I had to make the back tap as small as possible to even get it to fit all the way into the piston/head. you also HAVE to take the cylinder/injector recess out so that you can get the angle right. here's a pic

View post on imgur.com

What you'll also see in the pic is the fuel injector with its top snapped off because F$%^& rust. So, one problem solved, another created. I even used the damn tool and everything.

[wcs531]

Wow I havent heard of that happening to injectors, hope you can get it out without too much work.

It doesnt look like there are any threads to grab on to, maybe its possible to make threads with a tap or die on what metal you have there so you can get a slide hammer on it?

Not sure about the gas x5 but at least on the diesel cyl 6 needs an adapter of some kind to offset the slide hammer. If you try to force it you wont be pulling it straight out and will break much easier.

Also another note - the partitions to keep water out of the engine bay fail on the e70 quite often which would cause water to get into the spark plug area and injector area. Once you have this all back together make sure yours isnt leaking.

[analbumcover]

Originally Posted by wcs531

Wow I havent heard of that happening to injectors, hope you can get it out without too much work.

It doesnt look like there are any threads to grab on to, maybe its possible to make threads with a tap or die on what metal you have there so you can get a slide hammer on it?

Not sure about the gas x5 but at least on the diesel cyl 6 needs an adapter of some kind to offset the slide hammer. If you try to force it you wont be pulling it straight out and will break much easier.

Also another note - the partitions to keep water out of the engine bay fail on the e70 quite often which would cause water to get into the spark plug area and injector area. Once you have this all back together make sure yours isnt leaking.

Its really stuck in there. I was able to get a screw through the top flange part that broke off and into stem thats stuck - essentially "recreating" the injector" so that the injector tool can be used to pull. Started to pull on the injector with the tool and it stretched the screw until the head popped off. Broke 5 or 6 screws that way. Ordered the vice grip slide hammer tool but it won't be in until next week so I'm open to any other ideas you guys may have.

[wcs531]

With space being so tight back there it might be really tough with a vice grip slide hammer. I didn't realize how low profile that injector puller was until I just looked it up.

I would probably order another cheap n55 injector puller to sacrifice and find someone to weld it to the injector. Maybe use a torch on the head to hopefully expand the opening a bit(being careful not to heat up any plastic/rubber parts obviously).

[analbumcover]

just to close the loop on the fuel injector being stuck and to hopefully help anyone in the future.

the solution was cutting new threads M7x1.0 onto the injector stem. I kept cutting until I got half way down and stopped w/o backing up the die (really gets the die to bite in). From there, slide hammer-vice grip dealio (Astro Pneumatic Tool 78415). Locked onto the die and a few slides later it popped out. I also soaked the injector in liquid wrench penetrating oil and hand a helper hold the vice grips still while I went HAM on the slide hammer part.

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