Yamaha 200 hp 2 stroke head question

[murp1335]

I was cleaning my water jackets on my motor head and came across this hole on the bottom of the water jacket below the head. This is the starboard side which was running hotter than normal. Can anyone tell me what this is, is this a whole and should it be there? I guess I am losing cooling water out of this hole which is the reason it is running hot. Has anyone had this issue and what can be done about it? Thanks for any help!

 

[Oldsaltydog]

Did you intend to send a picture? There's not one. A picture would make this really easy to diagnose. Don't know if it's a tiny corroded pinhole, or a large hole that has a purpose.

 

[murp1335]

Did you intend to send a picture? There's not one. A picture would make this really easy to diagnose. Don't know if it's a tiny corroded pinhole, or a large hole that has a purpose.

Sorry about that, here it is. Thanks

 

[iang6766]

That is a corrosion hole, will be leaking water now you've cleaned it out but will not be causing overheat. Givecit a good clean down to solid material and plug it using a good quality epoxy putty to get a few more years out of it.Also remove the head covers, passages in there get blocked and common cause of overheat.