Well, its a lot of labor. Removing valve-covers, all timing covers. Alternator. Fan clutch, waterpump, thermostat, radiator. Intake manifold. Timing chain, guides, and tensioners. Than removing the head. Book says 15-21 hours for timing guide job, so add a few to remove that. Than the mechanic will have to see if the head needs miling. Your best bet is to get a used motor, and swap out all those new cooling parts and timing stuff to the new motor. I promise it'll be cheaper and easier. Specially if the motor is out side of the car. Not worth paying new motor money. Get a lower mileage motor with warranty. Specially if you over-heat the motor, things could be bad and you might as well need the head balanced and milled. Are you 100% certain its a head gasket?
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Last edited by BMW 3-SERIES; 01-10-2013 at 03:40 AM.