"Gull" lives in a part of AK that well....what most of take for granted, isn't there.

OP - take your time. I'm sure you haved so, look at the plug and be sure the threads look ok. Do what you can to clean the block side of the threads (?). From there. a bit of lube on the plug, then several "trys" at getting it back in.....it is a "feel" thing if it is threaded ok or if it is "cross threaded".

A bit of fine sand paper and a small flat head screw driver might take the "burrs" off the threads.

Again, just trying to give ideas....good luck.

 

The triangle file doesn't have to fit down into the threads. You just need something with enough of an edge on it to clean between each thread at the surface. Turn the plug, while cleaning between the threads, so that you end up all the way at the end of the threads.

 

I believe it should just be a regular metric bolt if it has a washer

 

It's metric, but a very fine thread. A thread file should do it, because it's just damaged - you aren't cutting new threads completely.

A thread file makes more sense because IIRC the plug is rather large diameter making it a very special-fine thread. Even though the pitch itself is standard, that pitch is rarely (or never) used with such a large-diameter bolt.

If you can't find a thread file, try a jeweler's file? But that takes more skill & care because the pitch & thread-form aren't "built into" the file.

 

Update: I ended up purchasing a new plug via online hondaparts place for $9.02. I was successful getting the new plug threaded in and got it screwed in and tightened securely, so of course am relieved and happy about that. It's in a dark and difficult-to-access location working underneath the car with limited space, with the CV axle right in the way below (for your arms/hands to get close) and the water pump connecting pipe pretty much blocking the ability to be able to get the plug centered by feel with your hand/fingers to start the threading. I think I more or less just got lucky and was able to manage it after struggling for a good while. The bunged up thread(s) on the old plug would've never allowed me to reinstall that old plug unless I could've managed to repair them, although I never did try because I didn't have (and was too much trouble/expense otherwise for me to obtain) any appropriate file to attempt it. Thanks though for the helpful suggestions in that regard.

The local hardware store here didn't have a thread file, nor did the two local auto parts stores.

 

Good deal. I forgot about that plug being hidden from view. With a steel plug and an aluminum engine block, guess which threads will get screwed up if you cross-thread it?

 

I suppose then the block threads would. I hope you're not suggesting it's likely my block threads are screwed up. I don't think they are. I'm feeling fairly confident that there is no cross threading going on. There's just enough viewing where I can actually see that I got my new plug threaded in all the way, flush and straight-on with the block. Plus, it "felt" "right" going in.

If the plug is steel (apparently) and the block is apparently aluminum, shouldn't the block threads have been the ones damaged instead of my plug? I still can't really understand how the dang plug thread got bunged up anyway; it just was; I noticed it after the plug more or less shot out when I finally unscrewed it from the block and a buncha coolant came suddenly gushing out. I picked up the plug out of the coolant in the tub beneath and noticed the couple of little sections of bunged-up (or collapsed or squished or whatever you wanna call it) on the thread right then actually.

 

My comment was more towards justifying (after the fact) your decision to get a new plug rather than repair the old one. Assuming the new plug screwed in without any difficulty, you shouldn't worry.

 

Okay JimBlake I getcha now. In retrospect, if I'd happened to have cross-threaded because of trying to install my old plug after "repairing" its threads improperly/imprecisely (especially being inexperienced at doing such and/or without just the right tool), there stood a good chance the block threads would've got screwed up, so perhaps by using a new plug instead I avoided that possibility.

I'm not worried, now. I actually slept good last night for the first time in over a week (since my first post this thread on Nov 9):

 

Glad you got it

Sorry for the "late" thought I e-mailed.......we're getting hammered early for winter stuff and as I was working on that today, my "thought" came to mind.

Anyway, again you got it in. I hope the rest of the story works out.