I just swapped in a jdm B18C1 into my 93 DX Hatch everythings working great except for when I hit WOT it begins to overheat. The Haynes manual has troubleshooting help for overheating...

1. Insufficient coolent in system. (full to the top)
2. Radiator core blocked or grille restricted. (brand new radiator)
3. Thremostat faulty. (replaced)
4. Electric coolant fan blades broken or cracked. (perfect cond.)
5. Radiator cap not maintaining proper pressure. (seems to be working fine)
6. Ignition timing incorrect. (no clue)

When we swapped we didnt think changing out the water pump was necessary since we were told it only had 40,000 miles. Could the water pump be the reason? Or could it be the rad cap or ignition timing? We cleared the pressure release valve on the block til the fluid was coming out as a full stream. Maybe that was wrong? Thanks for helpin in advance.

 

Check your temp. sensor for wiring/proper ground. Check w/ ohm meter/replace.

 

So far that seems to be working fine. It was weird because when I was checking the fluid in the radiator itself, the coolant was cool in the radiator. Maybe its the water pump not flowing it through? Im confused heh, I wanna drive this so bad, but this is the only thing holding me back. If anyone can give anymore suggestions that would be great.

 

just drive it and blow it up, call it a day

 

Are you sure you installed the t-stat correctly?

 

if the coolant is cold than its not circulating throught the system, check to see if the thermostat is a defected.

 

i'm thinking air in the system, bleed the cooling system properly... does your fan starts, if not, try jumping the fan motor, if it work then I would think fan switch, the sensor next to the thermostat, but if of course there is air in the system, this switch wont work properly

 

check your thermostat boil hot water to 300 degrees and drop it in if u see it open its good if not then its bad

 

try a lower temperature thermostat man. that worked for me

 

ill be checking all of these things today, i just got out of work.

ill update soon if i find out the exact problem.