i reacently bought a swap fro my 92 civic, when i had a b16a it never overhated at all, now i have b18c1 built(ls crank, rods, B16 pistons) and it over heats over a few days? i have replaced everything, fan switch, radiator 22t water pump no leak from hoses, OEM thermostat. temp sensor on the head and radiator cap.

the car runs good, the problem its that it pushes the water to the resevor and then when sitting at a light it begins to overheat. i donot know how to approach the problem anymore, i begin to think that it might be because the car might be running lean? but i dont think that it would be that dramatic as to overheat the car... i dont know what the problem could be. please help!! i think that the car might have a block guard? but i am not sure as i was not the builder of the engine...

 

Does the car overheat while your driving it? Or just when it`s idleing?

 

only when ideling... i have taken the car on roadtrips and it donsent overheat on highway, but as soon as im off the needle just rises..

 

It sounds like the fan. Check the fuse, it could be blown. If its not, check the obvious and make sure it plugged in. If it is and it still doesn`t work, than test it and see if its getting power. If it, and it`s not spinning, then the little fan motor is prob dead and you HAVE to get another. Anyone correct me if Im wrong.

 

Does the fan work? Air bled from the system?

 

He did say he replaced the fan switch.

When idleing, can you hear the fan come on, if not go check to make sure, eventhough new fan switch doesn't mean that is the problem.

I would def go the bleed route.

I have the same problem.

Another scenerio could be the headgasket going as well, might want to do a block test.

 

Doesn't mean the fan works.

 

I know I typed that

 

Im having the same issue, im thinking it just needs to be bled properly, i have a stock
b16 eg9 sedan turbo.

 

yes fan does work and i also have it wired to the AC fan so when i turn on the ac both fans come on, ive also bleeded the system like 10 times and nothing...

 

So you bought a car with a built engine but know nothing about it? Compression test it.

 

Also block test it.

 

if the fan is wired to the ac then it will only come on when the ac does. the fans cycle at different intervals.the ac fan kicks on when pressure goes up in your system. If you have it hooked up this way your radiator fan will only come on when the pressure in your ac sytem goes up and not when your engine temp goes up. this seems to be your issue. either hook it back up stock or wire it separately to a toggle switch. hope this helps

 

well its hooked up to both this way itll come on for both instances and both intervals