It took me a few days to come up with The Theory, and it was a beauty -- an example of deductive reasoning worthy of Hercule Poirot. What if we had failed (not having the special installation tool) to seat the timing gear fully? The cam would have excessive end play. The lifters are slightly offset on the cam lobes so they'll spin in their bores; therefore, as each lifter climbs its lobe, the cam is thrust forwards or backwards. The rude banging was no doubt the sound of the cam alternately hitting the rear of the block and the retaining plate in front, progressively getting worse as the oil warmed and thinned. The Theory fit all the facts and didn't rely on some preposterous coincidence to explain anything. I would have bet real money on it.

Mark heroically dispatched his own personal timing gear installation tool from Michigan via Priority Mail and, after two weeks of sitting quietly in our leaky garage, the 1800 once again came apart. I couldn't see anything wrong with the original repair, but the permissible end play is far too small to see in any case. I very, very carefully extracted the timing gear (no marks on the fiber at all) and -- this time -- removed the cam retaining plate and the spacer behind it for cleaning and inspection. There was simply no discernable wear on those parts at all, so back on they went. Mark's tool then pressed the gear very neatly into place, leaving no shred of doubt that it was on all the way, for absolutely sure.

A half hour later, the smoothest-sounding B18 in the world again came to life. After a few minutes' warm-up, I noticed a tiny little tapping noise. A few seconds later, it had become a distinct clacking noise. A minute after that, it became a Well, you know the rest of it. So much for The Theory.

For the life of me, I couldn't think of anything more to do that didn't require pulling the motor. Even if I came up with a way to diagnose the problem, it wouldn't be anything that could be fixed with the engine in the car. It was clearly time for another unclub social, and a major one.

It so happens that since last spring my engine stand has been occupied by a B20E motor from a 142 the unclub parted out. The details of its condition were unknown, but it had sounded OK the one time I'd heard it run. I'd originally intended it as a replacement for the 1800's B18B until a little carb work and tuning had made that B18 run gangbusters on Track Day -- I wasn't about to mess with something that worked that well. Next, I'd had plans to put it into the 122S as a replacement for its half-baked "performance motor" (see How Not to Build a Motor in this issue), but I never got beyond scrubbing 29 years of grime off the thing and accumulating a lot of small bits and pieces needed for the swap (new manifold studs, oil pump seals, plugs for the injector holes...). Apparently, Uncle Olaf liked the first plan better.

On the appointed Saturday, therefore, our driveway was once again full of unclub Volvos (and Shayne's truck -- someone had to bring the hoist, after all). I'd done all the prep I'd had time to do, which consisted of cleaning up the shop in the basement (the Chamber of Horrors, as Marsha calls it), locating and laying out all the accumulated bits and pieces on the workbench, and giving the "new" motor the best paint job I could manage by flashlight in the garage the night before. I got up early (for a Saturday), and was just finishing a 90-minute scrubbing out of the B20's oil pan (and I'd thought the motor was filthy on the outside!) when the guys arrived to remind me that we'd have to use the B18's pan if I wanted to have a place to screw the oil temp sender into. I knew that last spring, but with all the deducing of Theories and switching of plans, that fact had vanished into the mental ozone.

Cleaning the B18's pan was mostly a matter of scraping lots of little brass flecks and slivers out of it, obviously the shreds of some bearing or other. So much for preposterous coincidences being too great to happen. That's why they're called coincidences, you know?

Cameron was sure we'd be test driving the car by evening -- we'd done lots of motor swaps, although never on an 1800. It turned out to be less simple than we thought, but we were fortified by Marsha's pasta with peppers and grated Pecorino, so by nightfall the B20E was indeed sitting pretty on new 164-style mounts.

Many hands may make light work, but they also make a big mess. I tend to clean fasteners as they come off the car and sort them so I'll know where they came from later. One of the other guys likes to start them back into the holes they came out of. Another likes to put them in little piles on the floor; another throws everything into a cardboard box for later evaluation. I spent much of Sunday morning organizing all this so I could work with it, discovering that the radiator was still half-full of coolant (oops!) and realizing that I had no idea how to put the hood back on. I certainly couldn't complain, though; the big part of the job was done, and done right. I could take it from there.

This story doesn't have a happy ending, because it's not over. However, we can leave it at a happy point. I don't know what let go in the B18; it's now on the engine stand (with a very clean B20 oil pan on it) and I'll get to it when I can. The 1800 took me to work the Thursday after the swap and the motor just purrs, almost like it's electric. I was wearing a Band Aid on my right index finger at the time; Uncle Olaf finally did insist on blood before he was happy with the new heater hoses. There's a lot more punch in the mid-RPM than with the old motor and we'll see about the high end once a much larger exhaust system has been fitted. I have a Good Feeling about the car's future, once again.

Our 122S got its day in the garage and is much improved for its de-Weberization (Scott Sowell, thanks a bunch for the perfect rebushing job on those SU bodies). Marsha is driving it happily and complaining about slow drivers in her way. The overdrive works great once again, and every time. The right wiper is still dead, but I've got the parts to fix it. The VW bus just sits there quietly for now -- but that's a saga for a different magazine, and not one I'm likely to publish.

Spring is almost here, and all goes passably well in Cascadia.