Ray/Bror/mph,
Thanks for your feedback on my cooling system weirdness.
The first episodes last year didn't closely follow any maintenance on the cooling system. I did bleed the system, and the problem didn't recur, but it was just about that time that the weather started cooling, so I was never sure if the underlying problem still existed. (The heater symptoms were no longer in evidence, but since I couldn't duplicate ambient temp at the time of the problem, I couldn't be sure about the "overheating" aspect.)
The next time I took it in to a shop (for new tires), I asked them to check for any evidence of head gasket leaks, which they didn't find (I'm not sure what they looked for exactly). They did recommend changing the fluid, though, based on pH, and I did have that done. I suppose it's possible that that shop left some air in the system again, so I'll try bleeding again.
So far this year, I've had only the one case of "bounce," a couple weeks ago. I think the heater is working okay.
Everyone,
As for the rest of the report, does anyone have any further comments on wear metals, oil filter choice, or oil weight? At this point, I think I'm sticking with Red Line 10w30 for the summer, but I might try an Mobil 1 filter to see if it makes any difference in "insolubles." I also have one Ultraguard Gold UPF1127--I really hope it doesn't show outstanding results, since I can't get any more of the darned things!
Thanks,
Andy