I recently purchased a 2 horse 1983 evenrude. Took it out for a test run, after dumping tank new gas mixture and a bit of sea foam. Runs very well. I did some minor adjustments on both idle mixture and high end knobs that stick out front of unit. While adjusting high end I leaned it out a bit and motor really took off. So, I richened it back up to slow it down and it runs fine. Is this the right proceedure? I beleive it's rich enough so motor dont burn and plugs dont foul.