I was awoken by Mrs Shop Teacher at 5:20 am, because we’ve got no hot water. The pilot light will not relight. Gadamn it Skeeter.
I consulted with my plumber friend, aka lapsed Opponaut Birddog. He said it was likely the thermocouple, a generic part that can be had at any proper hardware store, and gave me a few pointers for how to tackle the job.
I headed to the local Ace at lunchtime, and dropped $12 on the part. After I was done with school, I drove straight home to tackle it. The burner unit being self contained, it was a bit trickier, but four torx screws and three sizes of wrench later, it was out. The thermocouple did indeed look pretty crispy.
Some persuasion with a set of channel locks and a side cutter later, and the old one was free. Now the challenge was to get the new one back through this rubber plug.
The rubber was not pliable or forgiving at all. I consulted again with Birddog, who suggested what I was wondering if it was OK to do. Put a slit in the side of the plug.
That worked, so I buttoned it back up, and crossed my fingers.
Successful operation doctor!
Whelp. That was a huge pain in the ass, but it could have been a lot worse.