I think a big factor for if and when a head gasket goes is if the car has been sitting for a long period of its life, and if the coolant has been neglected. I recently had to replace the gasket on my 1980 with only 145K. Upon talking to my mechanic, he showed me the bottom of the head itself and how the collant tubes had been enlarged and eaten away so much that they actually broke into the cylinder chamber. Aparently this is common in cars whose coolant hasn't been changed regularly because the anti-freeze will turn acidic and begin to eat away at the aluminum of the head. In my case, low mileage didn't save me. Recommendation was to change the coolant every 30K, and to always use distilled water with antifreeze. Aparently minerals in tap water can also cause damage over time.

So in the end, if you have a car that is 24 years old like ours, its probably a safe bet you'll have to look at the had gasket in one form or the other. Either because the car was taken care of and has high mileage with a naturally worn out gasket, or the car is low mileage and therefore had to sit for an extended period of time and gotten eaten away in that maner.

Jason

1980 245 B21F M46