Thanks for the two replies.
Tim, I did immediately change back to SAE 30W at the time I replaced the dipstick seal (I initially blamed the problem on the Synthetic oil). Not to argue the point, but the Briggs owner"s manual for this engine actually "strongly recommends the use of synthetic oil", but I"m not a fan. I"m to the point of just pulling the heads and visually inspecting the head gaskets as I have wasted a lot of time trying to diagnose this problem to no avail. The thing doesn"t start pushing oil until she"s warmed up.