Looking for opinions here. Does anyone think this cylinder head is cracked from this picture? The coolant reservoir gets milky. I should have tested it before taking out the thermostat but didn't. Any suggestions on testing it while open like this or how I should fix it? Should I use K-seal or water pump and thermostat RTV silicone to seal this "crack" in the picture?

 

I'd just go get a used head from a pick and pull and get it cleaned up and install it........

 

A automotive machine shop would use a dye to test for cracks in an aluminum head.

But that looks like a crack. And a porous casting. Coolant reservoir getting "milky" IMHO condemns the head.

Think Yoshimura_1 is on the mark with his advice and I would 2nd it.

 

Thanks i wouldn't even fool with that.......Get another head and order some valve seals make it happen.....