I just got this Poulan 42 cc engine that I am going to convert. It came out of a Poulan Pro 4218 chainsaw. When I took it apart I noticed a second butterfly valve above the carb. This butterfly valve only opens when the carb is at full open also After removing the carb and adapter I noticed another port above the intake port.

Question 1 Is this port for decompression to allow it to start easy or is it for something else?

Question 2 Since I'm going to make a new carb adapter anyway can I just cover and seal this port up?

Rob