I think your idea about the draining is cool, I just don't like cranking, even if there are 7 quarts in the crank, I just worry that when the sump kicks in, it's going to channel the air from the cooler that would normally splash the rods and cylinders but instead just splash it with air. Just because the ignition isn't firing, your still experiencing a lot of friction and with a potential dry spout, it's a little dangerous. A friend of mine that used to build race cars came over once while I was changing the
oil last time, he said I should fill the
oil filter with fresh
oil before spinning it on, he didn't say anything about the oil cooler, let's see what the rest of the cobra guys say. I suppose that you could diconnect both lines (away from the cooler) use the compressor to force the old out, but then use some kind of vaccum pump to pull the new stuff through, my guess is that the consensus will be just to live with that residual oil. There is probably 2/3 court in the fins and maybe a half a quart in the lines, that generally don't drain to the pan (gravity won't help with the lines. The best would be if there is a drain plug on the cooler, then you could simply fill it back up with just one of the lines.