Mercury classic fifty outboard stalling

I recently received a 1988 Bayliner Bass with what I believe is the original Mercury "Classic Fifty" 45hp outboard. I was told by the previous owner that the engine had been serviced this spring. I took it on its maiden voyage today. It started with a little coaxing then ran fine. I drove it for 45 minutes, mostly at full throttle with no issues. As I entered a no wake zone near my dock I eased the throttle back to idle. The engine died. It would not restart until I pumped the priming bulb and experimented with choke and fast idle settings. It then died again and I had to repeat the process several times to get it to my dock. Any suggestions would be greatly appreciated.