Engine Going Through Coolant Like Crazy, But No Leaks?

Does the coolant overflow bottle bubble with the car at operating temp? Does the coolant in the bottle smell like exhaust?

Head/intake gasket,cracked head/block are my guesses.

Go buy a chemical test kit at auto parts store. It will smell the exhaust gas in coolant if it is ther. It will turn color. If ur intake gaskets leaking in u better take care of it or u will have bent valves. Pressure test cooling system

if you got a leakdown tester push 100lbs of air in the motor cold and looks for pressure in the coolant system. when we start loosing a head gasket we can do it that way

All good advice. Here is what to do

Go to Advanced, O'Reily, Autozone and rent a coolant pressure tester and coolant exhaust gas tester. Both are free with a deposit. You will have to buy the blue liquid for the exhaust gas tester.

You can test your radiator cap an coolant system for leaks. Easy to do- use the adapter for the cap and see if it holds 16lbs. If not , the cap is bad. Then put the tester on the radiator opening- again pump to 16lbs which is the same pressure as the cap- looks for leaks- leave it on and see if the pressure drops over 15-20 minutes. Leaks could be from many places- hoses, overlow, water pump,radiator, heads, block, thermostat. If it does- you have a leak internal or external. If you don't see coolant on leaking then either it is an intake or head gasket or cracked block or heads. Is the car running normal otherwise?

Next- to test the coolant system for exhaust gas- that means the head gasket is bad and exhaust is seeping past it into the coolant system and likewise coolant is burning off into the exhaust. Notice white smoke at startup or while driving? Water dripping out the tailpipes? Spark plugs washed white? Does the car temp run high or has it overheated? Bubbles in the overflow or radiator when the car is idling? All signs of a bad head gasket.

Anyway- to use the tester. With the engine off, remove the radiator cap. Remove some coolant so there is a small gap of air between the top of the radiator and the opening. This is so the tester will pull coolant gas not coolant. Start it up to operating temperature with the thermostat open. The radiator cap should be off. The coolant should NOT puke out of the radiator unless the head gasket is really bad. The tester will fit into the radiator opening. Put the blue dye into the top part of the tester and squeeze the bulb to create a suction. It will draw coolant gasses from the radiator. PRAY to the car god that the dye does NOT turn green, If it does, you have exhaust gas in your coolant system= a bad head gasket.

I'd stop running the engine, if the coolant is going through the engine and mixing with the oil you'll destroy the rings and the bearings (if you haven't already) and there is no easy fix for that.

A block crack is unlikely, when it happens to one of these 302's it's usually catastrophic and the car won't run. With that said, ruining the bearings is as bad as a block crack.

Does the oil on the stick have any white/milky look to it?

I recommend you go back and read my post again.

Before you spend a lot of money, the white smoke from by the shifter sends up a big flag! You really need to do the pressure test, AND get the coolant dye that shows up with a black light. You could have a heater hose to heater core leak that runs down the fire wall and onto the exhaust while the car is hot. That leak will not show up on the floor, is hard to see, but will light up like a Christmas tree with dye.

If it is coming out the tailpipe, you might have a bad convertor/H pipe or some other exhaust leak. CO poisoning is worse than coolant in the oil. And it sounds like it is not going that way by not having milkshake like oil. It could still be a head gasket leaking only into a combustion chamber, so look at the plugs. But my other ideas are a lot easier to fix!

Have you checked the freeze plugs ?...they may be causing the coolant loss.