Exhaust manifold discovery?

[TXGlastron]

Good morning. With all the things I have learned about this boat I purchased, GXL 235 Mercruiser 5.0, I think I just found a serious issue. Hopefully I’m attaching a picture as well. Is this my exhaust manifold cracked?

 

[Lou C]

ahhh, wellll...YEAH
Was this boat winterized? If so, how?
if that's cracked check the other manifold and the sides of the block on both sides, as well as checking for water in the oil after firing it up.

 

[airshot]

That is a pretty serious crack, hate to see what the rest of the block looks like !! Quite noticible...you didn't see this before purchase ??

 

[TXGlastron]

I don’t see any other issues on the block, and the motor runs well. However, I’m thinking this is not safe at all to use and must replace. Am I correct?

 

[Lou C]

of course!
that will fill your bilge with water in no time!
how long have you owned this, & has it been run yet?

 

[Scott Danforth]

That is a classic example of thermal declination material breach due to volumetric expansion

Your block is most likely cracked too

If your block isnt, buy a lottery ticket