Water from 3.0L mercruiser

[conklinje]

I have water coming from the passenger side of an MCM 3.0l mpi. Looks like a plug fell out. What is this and how do I repair? Thanks.

 

[Bondo]

Ayuh,..... Welcome Aboard,..... Saltwater boat,..??..??

It appears several steel core plugs are rusting/ rusted out,.....
Can't believe Merc used steel core plugs, rather than brass or ssteel,.....

 

[Bt Doctur]

is this the first time starting since winterizing? if yes, a core plug was forced out or if a rebuilt engine steel core plugs were installed and rusted out
Bondo, some of the new 5.7`s are equipped with SS core plugs

 

[EBRAMS]

Is that the bottom of the manifold?

 

[Grub54891]

Looks to me that the manifold drain plug is missing. If the hole is threaded, put a brass pipe plug in it,

 

[conklinje]

Thanks, fresh water boat. It was the first time starting since winterizing. Hole is not threaded. Any idea on how to plug it, can the steel plugs be replaced?

 

[Scott06]

Yes core plugs can be replaced but there is a reason it is gone . I suspect it was pushed out by freezing and you will find the plug in the bilge if you look carefully . Put a core plug in or a expansion rubber plug in see if there is other freeze damage normally this happens if you are not completely drained of raw water