Asking opinions on what weight oil to use is a never ending saga. I use 20W50, valvoline, and I am in Los Angeles.
However, I think regardless of the weight, there should be no problem in gettin oil to the lifters. They might be oil starved for 2 seconds at start-up, but if you are not getting oil to the lifters, I don't think a lower weight will help that much.
You need something to clean them with - and, like I said earlier, I tried Risolene (yellow bottle, 1 quart) and added that to my crank case. I think it helped tremendously.
btw - do you live in the US?
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