I'm not an expert but here are a few observations I had based on what you said in the thread.


First, it seems odd to me that the coolant could have slowly leaked out over time without you seeing the temperature gauge rise as the coolant level got lower. Have you confirmed that there's no coolant in the radiator? Is there any sign of leaking from the throttle body? If leaking was really occurring, you'd see a pretty good amount of residue near wherever it was leaking.


Second, is the engine seized or are you able to start it? If you're able to start it, I'd refill the radiator and see what happens. If your oil is milky, there's a pretty good chance that the head gasket is blown or the head is now warped allowing coolant to mix with the oil. Overheating can certainly cause that.



Last, it would definitely be helpful to get a leak down test and compression test done. That's assuming the engine isn't seized. If it's seized, you won't be able to do either since they rely on the engine cranking (compression test) or turning the crank pulley in order to get the piston at the right location so the valves are closed (leak down).



If you can start the engine, I'd fill the radiator with coolant and change the oil. With the engine cold, open the radiator cap and see if you're getting air bubbles coming out. If so, you've likely got head trouble and will likely need a head job (lol :giggity. If it runs like crap it could be due to coolant getting into the combustion chamber. It could also be head trouble or bad compression due to damaged valves or rings, though I feel like that would be less likely.