Repair Blown head gasket

Ah, those good old three filthy engines as my mechanic friend used to call them. I've done that job on my son's '85 but it's been a while. Honestly, there's just too much information needed for me to be able to walk you through it online; my best suggestion would be to pick up a Haynes manual. That's what I used and it got me through the repair just fine, but be aware that it's a pretty big job.

Main thing you have to do is pull the intake and exhaust manifolds; of course those are all tangled up with fuel lines, coolant hoses and electrical connectors, not to mention the distributor, so there's a lot to do to get to those heads, plus a lot of gotchas to watch out for like keeping the push rods in order so they go back where they came from, along with the lifters themselves as well.

Always a good idea to check the head for flatness when it's off, and if you have any reason to suspect a crack you should take them to a machine shop to have them Magnaflux the head to check. Good time to replace the valve stem seals while the heads are off and examine the valves for any signs of burning or cracking, along with the valve seats too. Most head gasket sets come with the valve stem seals anyway, so you might as well put new ones on; there'll never be a better time.

Once you've gotten the gasket replaced, follow the tightening sequence and use a torque wrench on the head bolts, along with sealant for the gaskets on the water passages. I'd suggest a new thermostat just to play it safe, and of course drain and refill the oil and the coolant if there's been any mixing as a result of the busted head gasket.

That's about all I have for you; if you have specific questions along the way I can either try to remember what I did or consult my Haynes manual for an answer. Good luck and let us know how it goes!