funwithfuel
Senior Member
That is poor coolant maintenance. That's what happens when you mix EG coolant with OAT coolant. You get silica dropout. A pressure washer through the coolant passageways should knock that loose and clean right up. It won't help with the piston cooling jets. You still have that going . Your sealing grooves all look to be intact. That's why that piston scored also. The liner got hot and squeezed it. Would be my guess. Worse case I've ever seen. I'll bet there's some stop leak in that crust. Which brings to mind, dont let the radiator shop just check your radiator. Make sure to have them remove the tanks and rod the core out.