Uh oh...

So I changed the spark plugs in my 2013 tacoma today and on the last one I broke the bolt off that holds the coil on the spark plug. Pretty sure I cross threaded it while tightening it up. I took the truck for a lengthy test drive and it seems to run really good. I’m not sure if it will be ok like that or if I could put some high temp silicone on it to hold it in place. I know the correct way to do it would be to drill it out and tap the hole. However, I’ve never done that before and don’t really know how.

 

As I said, I’m not familiar with how to do that. Is there any particular tools I would need besides a drill? Thank you for the response.

 

A set of left handed drill bits.

 

I assume that would get the bolt out but how do I re thread the hole for a new bolt?

 

If you've never used an extractor before, I'd go see somebody who knows what they're doing instead. You could make a serious mess out of your valve cover there.

 

Using a left handed drill bit should be able to back the bolt right out.... or use a drill a normal pilot hole and use a ez out (that's the name) and you shouldn't need to rethread the hole.

 

thank you. Is there any thing wrong with leaving it like that temporarily, until our shelter in place is over? I don’t drive it much other than to the store and back?

 

you don’t think I’ll need to re thread it if it was cross threaded? Thank you.

 

Did you cross thread it when putting it in?
Edit. I would try getting it out and with s new bolt, move slowly and figure that part out if need be. Shouldn't be too hard to tap a new thread once old one is out.

 

Yes, I’m pretty sure that’s why it broke.

 

Get the old one out first.

 

If you decide to extract the bolt, put some painter's tape over the cavity the spark plug sit in to keep any debris from falling in there.

You can probably drive it as is, but the coil could pop off the spark plug and you'd have a mis-fire.

 

If it's cross threaded, an ezout most likely will snap also. Then you're left with a hardened steel bit in the center which will be impossible to drill by hand.
Grind it flat, center pinch it, drill out with progressively larger bits until just short of hitting threads. Then pick out remaining thread bits with a punch/pick, trying not to damage the aluminum female threads.
Another trick is to try drilling it out with left hand twist drill bits. Will sometimes come loose while drilling.

 

Thank you. Do you think some high temp silicone around the coil would help to hold it in place? Thank you for the tape idea. Will definitely do that when I take on the task of repairing it.

 

This guy knows what he's talking about. The chance of success with a professional attempting it is about 62%. The chance of a novice having success is about 18%. If you drill it off center, your chances just dropped to .003%

With that percentage, it's probably not worth paying a professional who will charge you for his time and may not be successful.

If you really did crossthread it, you should be considering a used valve cover. If it snapped from overtightening, and not crossthreading, you may be able to pull a rabbit out of a hat and get the broken piece out.

 

I wouldn't use silicon, but that's just me. It seems like that could end up leaving a mess.

 

Are valve covers very difficult to install? Thank you for the info. I’m sure I cross threaded it. I tightened it pretty tight and though it was all the way in...I noticed the coils was still moving around, so I went in to tighten it more and that’s when it broke.

 

Yeah, if the bolt got tight and the coil was still loose, it's pretty much for sure that you crossthreaded it. Valve cover replacement is probably 1 of the simpler jobs on a Taco. Not as easy as changing the oil, but easier than changing a transmission.

 

Ok, that’s good to know. I tried to find a YouTube video of it but couldn’t find anything for a 4.0L. Guess I’ll just try it on my own. Thank you for the info.

 

Do you happen to know if a valve cover from a 2009 4.0L tacoma would be the same for a 2013?