Frost plug popped out again?

[Porkchopz28]

I recently acquired a free boat… for many reasons the boat was free one that is concerning me is the frost plug popped out on the previous owner twice. Popped out when on the water then after having it reinstalled it popped out again. What would be the reasons for a frost plug to pop out in the first place on a 1984 Starcraft 19’ OMC V6 3.8L? Corrosion, over heating, stuck thermostat?

 

[jimmbo]

Improper Installation, Wrong Plug perhaps

 

[alldodge]

Agree, could also be there is an issue with the edge of the block surface. Could use one of the compression type, but change all the hardware to stainless steel. Would also remove it after a couple years to see if its holding up.

https://www.autozone.com/parts/exte...eze-plug/dorman-freeze-plug-kit-2604/522473_0

 

[jerryjerry05]

Try the expandable rubber plugs and see if that pops out?