1977 century with OMC freeze out plugs

[Ajstangl]

My 1977 century freeze out plug behind the starboard engine mount is leaking. Engine 990230G. I used it about 11 years ago in salt water and after that trip two of the freeze out plugs were leaking and replace by a mechanic I don't know which ones he replaced. Any advice on the best way to get at this? And should they all be replaced. Also the bellow was never replaced on the boat. Should I do this as a preventative it is 49 years old. And any advice on this job?

 

[southkogs]

I've never changed the freeze plugs on that engine.

But, you shouldn't have bellows on that drive system. That's a Stringer, so you likely have a boot there on the transom. If it hasn't been changed in 50 years, then yes - I'd change it.

 

[Scott Danforth]

if the core plugs rotted out, then the motor was replaced at one time with a non-marine motor

the ones from GM when the motor was new were brass

first, determine if the block is rusted, the core plugs pushed out, or was the block swapped to an automotive one?

to R&R a core plug, usually the motor will need to come out of the boat to do it correctly. at that point, I would get one of the rubber expanding ones.