I am looking at a 97 Deville with a cracked head due to a blown head gasket. The dealer is offering me this car for $4000.00 in reading some of the archived forums there are 2 options for this problem, either replace the motor, or try and use "time sert" to replace the head. I guess I want to know what the failure rate is when just replacing the head. If replacing the motor is the way to go where can I find a reputable salvage yard to buy a used motor? And what are your recommendations on used motors.

I guess i should mention that the motor is a northstar 4.6 vin code Y