Orange spark plug insulator

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I'm currently chasing a coolant leak on my 302, I determined that I was leaking at the head gasket on the passenger side so I deceided to check the head bolts. In order to do that I had to pull the headers and the spark plugs, when I pulled the plugs I found them all to have orange insulators and to be wet. Is this an indicator that the motor is eating coolant? Attached is a picture of one of the plugs, they have about 900 miles on them.

Thanks,

Mario