Do I have a cracked block?? John Deere 310A

I recently bought an old John Deere 310A that did not run (there is another thread on that). I got it running, but ended up with water in the oil and a "chirp" after a couple minutes. Suspecting a head gasket leak and seeing a plugged rocker arm as the cause I;
-Drained the oil last night (left the plug out to get as much water out as possible)
-Disconnected the intercooler lines and drained them in a bucket, also left open (which exit the pump below the water pump)
-Replaced the drain...

Do I have a cracked block?? John Deere 310A