Get a combustion leak tester. It will check the coolant for combustion gasses. I can speak from experience, a blown head gasket, cracked cyl head can cause over pressuring of the cooling system resulting in a failed coolant tank cap.
I would check that, and also do a cylinder leak down test. You might find something else is the culprit for having to replace the cap.
What coolant percentage are you running? To weak and I have found that it boils the water out of the coolant.
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I would check that, and also do a cylinder leak down test. You might find something else is the culprit for having to replace the cap.
What coolant percentage are you running? To weak and I have found that it boils the water out of the coolant.
Sent from my STV100-3 using Tapatalk