I bought a small aluminum boat with a 6 hp Sea King on it a couple years ago. The lower unit housing was broken, but it ran like a dream. I have since gotten ahold of another motor that is the exact same model and built the same year, and swapped the lower units on it. The other motor ran when it was put away, but had no spark when I tried to start it, so a few bolts to swap the lower unit seemed the thing to do. I hope to get it in the water next weekend, and I'm unsure of the mix ratio. There was a bottle of Quicksilver in it, and I have access to 90 octane E free gas. Model and serial number of it helps. From what I can find out, it was built by Chrysler Marine in 1966.
I've read that about the older Gale manufactured Sea Kings. Apparently Chrysler had quite a bit of variation in their specs in the 60s. And my guess this is with some type of standard engine oil? I guess I'm not sure what I should be doing with a modern TC-W3 oil. I suppose I could start at 24:1 and see what happens.
I had an old Chrysler 40hp that I ran tc-W2 at 24:1. TC-W3 fouled plugs at 24:1 when I idled a lot no matter what plug I used. I talked to a marine mechanic and he told me to run it at 50:1 with the better oil. I was too nervous to try that so IIRC I ran it at 32:1 with TC-W3 and had no issues.
I suppose I'm probably overthinking a bit. I'm sure there's been a lot of different stuff burned thru this motor in fifty years.
Oh yeah the new oil for 2 strokes is so much better than the old stuff, so you don't need to run it so rich. It would probably be fine at 50:1, but id go 40:1. Run it at that, and go a plug check. If it looks good, run it.
