I have an 88 Cherokee with a coolant leak towards the back of the motor.It only leaks when it warms and I accelerate but mostly when I turn it off after I've driven it around. When I turn it off it looses the most and leaks onto the headers and steams like crazy. I can't figure out where it is coming from I thought maybe it was one of the freeze plugs but it doesn't look like it. I could be wrong but I'm stumped I checked the hoses and I can't seem to find where it is coming from. Ive noticed when I'm driving and I see some steam behind me the the motor has a slight increase in tempeture then returns to normal.

 

sounds like a freeze plug to me. You won't be able to see/fix it unless you remove the transmission. Pic is from google

 

On old motors like that you can often look for the clean spot. Coolant steams away the old grease and oil. You might have to put a cooling system pressure tester on the radiator, pump it up and look for the leak.