Q: Car overheats occasionally and will not start

This car had about 250k miles on it. Engine was replaced last summer with an engine that had about 50k by Honda because it overheated and cause alt issues. about 2 weeks ago when I would drive somewhere and once I stopped, I would notice a bubbling, fizzing sound coming from under the hood.It just underwent inspection and all fluids were checked. Opening the hood, couldn't tell what it was making the sound. This did not happen every time and I assumed it was bc I'm in Texas, it's hot, and it's just overheating for some reason. before I could bring it in, I drove it maybe 2 miles 3 stops. was at 3rd stop for maybe 20-30 minutes and car would not start. Turned over but didn't start up completely. So I left it For 3 days. we decided to try starting it again to drive it to a mechanic and it started. No probs, no check engine.Mechanic suggested issue with valve cover gasket leaked onto starter but was really unsure.Did nothing bc we don't know what prob is

My car has 60000 miles.
My car has an automatic transmission.