so im having issues with the cooling system on a d16y7 in 92 4 door, list of new parts within the last six months:
radiator
hoses
oil and filter
opened up thermostat after i took the workin 1 out
water pump prior 1 was just fine
also to hard wired the fan to a switch
heater core was replaced within the last year and prior 1 was fine
why i do not think its a headgasket. oil is still as clean as the day i changed it and it seems the only way im losing coolant is out my overflow.
i swapped out the d15b2 because it was doing the same thing and i thought water pump, right after the y7 swap there was a period of time where i had no issues with the cooling system and now its back. could it be air in the system that just refuses to get out? faulty cap and overflow?

 

you can still have clean oil and a blown headgasket.

 

Oil in the coolant, or vice versa, is NOT the definitive sign of a blown headgasket. Did you test the coolant for exhaust gasses?

 

no oil and she doesnt smoke