After reading the many postings on the subject, I "cheated" and hot-wired my 1971 280 SL's CSV valve via an ON/OFF 12 V switch in the cabin. So now the car starts in the mornings on the first go. You cannot imagine my sense of accomplishment! (I had NEVER done work on a car before. Took me a few days just to locate the parts on the engine).
By the way, once hot, the engine starts immediately -- I use the pedal-to-the-metal technique.
Still, I'd like to replace both the thermo switch and its relay which, as best as I could figure out, are both shot. Can anyone help me with the part numbers involved?
Next, I will start looking into a backfiring problem that I have noticed when accelerating, particularly when the car is still relatively cold. Any ideas? Might one of the temperature sensors in the block be at fault? Or the "speed relay"? Or both? Where would you recommend I start my research?
Thanks everyone. This is a great group.