Thanks to all who posted suggestions on what might be responsible for the decrease in mileage that has recently occurred to the Wonderbus.
18.8mpg went to 16.8mpg. This shortly after I installed Tiger CDI and gapped plugs to .040''.Oh -- I also had a local shop repack and readjust the wheel bearings, and do some brake work at around the same time. Forgot to mention that.
My especial thanks to the wise fellow who privately e-mailed me and suggested that I /just might/ want to feel my brakes and bearings after a drive.
One front and one rear were quite warm. Dragging brakes. I'm back to the shop this morning to discuss the matter and have the matter corrected.
I could beat myself up for not having checked for this much sooner. But as anyone who has been around for a while, I didn't even knew how to change a car's oil a couple years ago. The Wonderbus has taught me a lot
-- usually too late to do anything preventative, but I'm learning, I'm learning.