another overheating problem

If you have been running antifreeze
Go to the back of the car,stick a finger into the pipe and rub it in the soot, then taste your finger. If it is sweet, the she's pushing coolant thru alright.
With the head now off, find the clean piston. That's the one that is making steam.
Check the chamber above it for a crack(s).
Push the piston to the bottom, and check the cylinder wall for a crack.
Look on the backs of the intake valves. You see any green tinge on one of them, or one that is washed clean.Also check the exhaust valves;both sides.
If you couldn't find anything then the head needs to be pressure tested.

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