I just had my engine in and everything hooked up ready to go but when we started it today it was blowing smoke(blue colour), and we then found that we had over filled the oil, and we drained it and refilled it again, and it still blowing smoke, then we though the oil was too thin and we refilled the oil again with thicker oil and a bottle of "stop smoke". And we cleaned the spark plugs which were full of oil, then started the motor again and it still blowing smoke, so does it mean this motor has cracked piston rings? we didn't have the tools to do compression test but we'll do it on Monday, anyway any other chance of blowing blue smoke but not a cracked piston rings? damn it I don't want to do it all over again...