If you're doing a flush, you'll have the coolant drained at some point. Open the thermostat housing & pull the lower hose over where you can reach it easy. Open the upper hose at one end or the other.

Use a garden hose to blow water through the radiator. It should flow right through. Not sure if you can use a small inspection mirror to get a look inside the radiator??

 

Changed the thermostat. Problem Solved! Yes!

Anything to watch (besides the temp gauge)? I probably should start saving for a water pump and timing belt job.

Thanks for all your help!

 

On a regular basis, squeze the radiator hoses when the engine is COLD. A bad radiator cap can allow water out into the overflow reservoir but won't suck it back in. That lets air into the system. You should be able to hear sloshing noises if there's any air in there. I do that whenever I check the oil dipstick.

 

well damnit. the car started overheating again.
Stays normal temp highway driving, but temp skyrockets when parked/stop and go driving.
I'm going to try and and bleed the system again.

Also, I didn't buy the honda thermostat. Just a regular aftermarket one (I'll never do that again). Could this be the cause?

Thanks

 

How about radiator fan operation? You say the car doesn't overheat when you're driving - there's plenty of air & the fans aren't needed while moving.

Yeah, non-Honda thermostat can do that, but the fact that it behaves properly when driving suggests the thermostat is OK.

 

make sure that both fans work..

 

Take a lot at the radiator core between it and the condenser if you haven’t already. Overheating at a stop is loss of airflow such as the fans mentioned but also the external core of the radiator. My 95 Accord radiator was coated with something organic that looked like cattails when they break up and overheated at every stop on a two year old radiator. Twenty minute cleanup and problem solved.

 

Ok. Diagnosed it.

Coolant was really low (both overflow and radiator). I topped off both and car runs cool like before.

-Fans click on
-Radiator cap is fine
-Bled some air out through bleeder screw

What worries me is that I have topped it off before when I changed the thermostat. Something is leaking somewhere, right? I am running more water than coolant (probably 70/30).

Car runs, just trying to figure this thing out.

Thanks

 

The radiator cap allows coolant to go over to the overflow reservoir. But almost as important, the cap makes it suck back into the radiator when it cools down.

Check for scratches & gouges in the 3 different rims of the radiator neck where the cap's rubber washers seal against. Also look for leaks in the hose going over to the reservoir. A leak there is like sucking through a leaky straw - you get a lot of air.

 

Ok, it looks like there is a very small amount of coolant leaking from the bottom of the thermostat housing. It should have sealed good, but looks like something is amiss.

Anyway, good to know where the leak is coming from. Now I just gotta figure out how to put a stop to it.

Thanks