How much gas in it?
I have the exact same engine and had numerous problems. Had stuff replaced and finally determined that it was probably vapor lock. Took care of vapor lock problem and all was fine for 1000 miles.
Suddenly stopped, restarted immediately, stopped 10minutes later. Changed fuel filters, refilled with 32 gallons of gas. No problems for 500 miles. Happened again about 6 times in 30 minutes. Put another 32 gallons in tank, no problems.
I feel that my fuel intake in the tank is not able to get to last 7 gallons steadily when it's sloshing around.
I'm going to get a new fuel pump in tank and they'll make sure the pump can get the bottom fuel out.