Holy crap am I screwed.
The problem is the joint between the exhaust manifold and the rest of the exhaust system. I believe that there were originally three bolts holding the flange in place, but what's left of them now are some weird tapering thing I can't describe simply but which emphatically do not hold anything securely. Because the hangers broke both at the catalytic convertor and the muffler, all the weight of the exhaust system (but for the rear four feet) is hanging from this joint, with the result that of course it popped open.
So here's what I must do, and I must do it today:
1) repair the hangers, somehow, so that they will support the exhaust system again
2) remove the remainder of those studs or bolts or whatever they are, and replace them with new bolts.
...of secondary importance to the latter is getting the correct gasket to put in that joint as the original one has perished, but I can handle a couple days' worth of hissing/rapping from that joint as long as it's not open the way it is now.
I got up early this morning and attempted to effect a temporary repair, but nothing that I had planned to try did any good whatsoever, and I could have simply remained in bed and achieved the same end. Gave up at 11:45 and hit the shower, and went to work, intending to chew things over with my boss and see if I could take tomorrow off and fix it then.
Turns out that the general manager is really adamant that no one who is scheduled to be there tomorrow miss work. Anyone who misses tomorrow is in DEEP SHIT and I have no desire to do any wading, myself, thanks very much. Boss suggested I go back home and get things dealt with so I can be there tomorrow, and I took his suggestion.
...and so my initial impulse, at 11:45, to call off and work on this shit, also turns out to be what I should have done.
I notice that I always have this shit happen in the middle of my week. Today is my Wednesday, and the pipe blew out yesterday; of course there's no fucking way in hell a muffler shop will be able to do anything for me without replacing 60% of my exhaust system and charging me $400 for it.
On the plus side, it turns out I can replace one $100 part and get one hanger back. Minus side, no one stocks it, and if I bought it today I wouldn't have any money left anyway, for things like gasoline and food. Argh etc.
So I get to cut and drill and replace bolts, and try to find a way to hang the damned junk up until I can order one of these pipes (Walker 53440, $68 plus shipping from rockauto!) and put that in.
And of course I've also found that the passenger footwell is rusting out. It never rains but it pours.
[many bad words redacted]
Mostly, he drilled one hole and bought some fasteners...but that was the crucial last step.
After the last post went up I hit the driveway and started working. Disassembly was pretty simple; the bolts holding the muffler to the catalytic convertor had been put on only a couple of weeks ago, and once I had the muffler sitting on the ground, the pipe and catalytic convertor just came right off the downpipe from the exhaust manifold, because whatever nuts had once held those studs fast to the manifold had long since rusted away. I was able to wiggle it out without having to remove anything but the upstream O2 sensor; and then I set to work on removing those sad, rust-eroded studs.
For five frickin' hours.
I managed, after a lot of effort and two trips to the hardware store, to get two 1/4" holes drilled where the studs had once been, and I'd gotten most of the third hole drilled, but I absolutely COULD NOT get the third hole bored to 1/4" all the way through. I tried four 1/4" drill bits.
Og came by sometime around 8-ish and--using the drill he uses daily with one of his 1/4" drill bits--bored the hole through in about forty seconds.
I immediately began reassembly and after I broke one of the brand-new bolts I'd just bought, we took a trip to Menard's for some grade eight fasteners (rather than the grade five I'd found at Ace) and then managed to reassemble the truck.
I took a stab, while it was still light out, at welding the hanger rod back onto the pipe. My first attempt was a cold weld and I knocked it right off with a wrench--not even a hammer--and then I ground back the weld and tried again. My second attempt came out better, much stronger, and off I went to the races.
...finally got everything buttoned up at 10:30-ish. My weld job on the hanger was pretty good but it wasn't all that great, and it broke during assembly; so at Og's suggestion I took a 3" chunk of 2x2 steel tubing, flattened it a bit with the BFH, and stuck it under the exhaust pipe to take the strain off the manifold flange. I secured it with the strapping I bought this morning; it's not going anywhere.
Started the truck, it was about as noisy as it has been; then I realized that I hadn't put the downstream O2 sensor back in. With that installed, the truck is quieter than it's been for a couple of months.
It was a ball-busting all-day job, exactly as I had feared...but it's done, at least well enough that I can get to and from work without risking hearing loss or a moving violation; and now the next time I have a weekend I can work on improving it. Get a gasket between the pipe and the manifold, for example, and maybe take that pipe over to someone who has a real welder, rather than a 110v flux-core rig like mine, which is not exactly well suited for welding thick steel like that hangar rod.
I could not have completed this job without Og's help. And he gave me some safety tips for working on the truck, things which had never, ever occurred to me; so from now on I'll do as he recommends, because he's forgotten more about fixing stuff than I'll ever learn.
Now, I'm going to go do some WoW.