Hey guys, swapped my rad out for a half sized unit as my rad cracked and i had a half size laying around from an old civic, ever since then its been overheating and its also not blowing any hot air through the vent, first thing that came to my mind was a thermostat , so i went to the local parts store and got one, put it in , bled the system and then not 2 minutes up the road after letting it warm up it overheated again and still no heat coming through the vents, ive since made sure all the hoses are clear/flowing good ,drained and rebled the system, installed the coolant temp sensor from the old rad where the petcock hole is on the half size, made the fan run off a manual on/off switch so its always running, put another new thermostat in just incase the other one was faulty, neither new ones seem to have any issues when inspecting, although they are a little loose in the housing/sitting in the rubber gasket/seat piece has anyone noticed this as well or is it just me getting the wrong part from 2 different stores? Figure it cant be the heater core being clogged because that wouldnt cause overheating as no coolant runs through it anyways when your blowing cold air on purpose , was going to go water pump route next but when i turn the car off after it overheats all the coolant in the rad and overflow resevoir are boiling so it has to be flowing through the hot block right? Also i figure the half size has gotta cool the coolant enough if i used it for a 1.6l d16 and it did fine , as the l15 is a smaller motor and takes less coolant, im stumped, if anyone could point me in the right direction that would be awesome, cheers

 

In your shoes I'd just pay the hundred bucks for the correct radiator so you're at least starting from square one with the known-proper part.