Fridge pilot goes out

Also check that the thermocouple is not loose. That can cause your symptoms. If loose, check the book on how far into the flame the nose of the thermocouple should be, reset as required, and tighten down.

While in there, make sure you clean the terminals for the thermocouple on the control board. That device is a very low resistance and corrosion can slowly work it's way onto the spade connectors so the resistance rises over the years.

Pulling them off at the control board, cleaning them, and perhaps squeezing the female connectors a bit so they fit tighter on the control board is a maintenance procedure to help prevent symptoms like yours.

I've also seen the thermocouple wires loosen in their respective terminals so recrimping is called for.

Do you have a pilot light or an ignitor that lights the gas when needed? Either way clean out the tube coming off the gas valve. It's likely full of rust particles. Also tap on the stack going up above the flame to knock any rust loose. If you can remove the gas tube that would be good or you can used compressed air to blow it out. We had the same problem on our previous MH. After cleaning it ran perfectly.