97 civic cx hatch
00 B16A2/OBD-1/P30 ecu
no major engine mods, just a ebay intake
No white smoke

Ive been having many issues with my cooling system for a while. Today i decided to fix it. I replaced the thermostat, fan switch as it wasnt working and did a coolant flush.

My exact process was:

Disconnect battery, drain coolant, remove lower rad hose, remove ground on thermostat housing, removed thermostat, replaced with OEM Honda thermostat (made sure it was in correctly), replaced fan switch (not oem), reattached ground and lower rad hose, filled with coolant.

For the flush, I filled the rad, cracked the cap open, let idle for 30 minutes, then drove about 5 minutes and topped it up, drove another 5 minutes and topped it up, tightened the rad cap and drove about 15 minutes home.

The car never got up to operating temp when left to idle for 30 minutes, the fan didnt turn on once and the t.stat didnt open (lower rad hose not hot). As i was just getting home after 25 or so minutes it just seemed to get to temp. But lower rad hose was still not hot, it was warm in the middle section of the hose, but i dont think that counts as being hot. Also seemed like i had evaporating coolant once i got home, there was steam coming from the rad and it got in my mouth and was defiantly coolant.

Yes i remembered to plug any and all sensors back in, checked for leaks and saw nothing.

Any ideas as to what could be wrong?

 

Check to see if your fan is working.

 

I just let the car idle for 30 minutes. It never got to proper operating temp, came close. The fan never came on once in the 30 minutes. I drove around for 10 minutes, temp didn't change. And I'm not sure if the fan came on while driving.

 

tony is talking about unplugging the fun plug and directly connecting it to the battery for a moment to see if the fan operates.

The fan is a 12V dc fan so will run directly off the battery if it is operational.

My thought is I would do the boiling water test with the thermostat to be sure it's not a defective one. Not likely but does happen sometimes regardless of who makes it.

 

Thermostat could be defective....which is extremely rare if you got it from Honda. But it can happen.

You're smelling coolant because you spilled it on everything. Wash the engine bay when you're done fixing the issue.

 

I've ran the with the fan switch jumpered out for 2 months, so I know the fan works. I'm currently boiling the thermostat now to see if it opens properly.

 

Just boiled the t.stat and it opens and closes correctly.

The only thing I can think of is an air bubble. But I made sure I bled the system well

 

Based on your method of bleeding the cooling system, it was done incorrectly. Follow the service manual procedure. It may also help to raise the front end during the procedure.

 

Okay, I'll try bleeding the system the service manual says. I'll jack the front end up a bit as well

Thanks!