I cannot get the above engine to run long.It only seems to run till it burns all the fuel that I put in the carb to start it.The (H) needle is turned out 2 1/2 turns and I do not know how far the (L) needle should be turned out.I read a post about closing the (L) needle and putting a fuel line on the nipple where the fuel enters the carb and blowing and backing out the (L) needle until I hear air but this does not seem to work for this engine. It has very good compression. Thanks MJ