Looks like some black junk in the main jet. If it is, it would be wise to address the fuel lines. They've got a nasty tendency to come apart internally, and where's the junk end up? In the jet(s) usually.
-Side note. GF and I were fishing a local river. Current was swift. Where we was at, just down river from us was a class 2 rapids, which I won't take my boat over for obvious reasons. Another boat almost identical to my tin decided to take it on, turned it around (motor down river using power to address the rocks) and did well until at the last second it hit a rock, hung up, and the stern went under. They came out of the boat and floated down river out of sight. Her and I took off as fast as we could up river toward the dock to let the guys at the dock what was going on. We get within a hundred yards or so of the dock and the motor dies. She's sitting in the pedestal seat (against my advice) when it died. Out she goes into the drink, right over the front of the boat. Got her back in and to the dock, told the guys, they took off in a jet boat at mach 2. I get loaded, drove home, she's mad as a cold/wet hen the whole way, so I stuck the boat in the shop. Figured lost a fuel pump or line. All that was fine. Pulled/disassembled the carburetor and found a TICK in the main jet. Dead obviously, but now how'd that little booger get in there? Never did figure it out....and ain't had a problem since.