I posted on g2ic, but I'm copying the post here to see if anyone has any comments

So I've never had a problem with the heat in the car, ever. It's usually so hot I have to roll the windows down or put the dial half to a third of the way.

But two days ago I had to go to my final exam at 6pm, and it was the coldest night of the year so far. The car usually doesn't take long to warm up, but it was taking longer than usual, yes I took into account that it was freezing outside. Well, I got about 3 miles down the road, and heater is still freezing and the car starts to overheat. 50/50 coolant if your wondering

I didn't drive it after that, just left it in the nearest parking lot and had someone pick me up and bring me. Well, the first thing I could think of would be the thermostat so I just replaced it. Took it for a test drive, and again the same thing. And still no heat. The wierd thing is if I shut it off and turn it back on right away and it's back to normal driving temps...does this make any sense??

There's no leaks anywhere. I just replaced the timing belt, tensioner and waterpump with honda oem last month. So I can't see my waterpump failing that quickly. If I open the radiator cap it's still moving the water in the radiator. I also noticed nothing is coming out from the bleeder valve if I open it. I did drain the coolant and put fresh coolant in. And I've also noticed the lower hose is cold.

It doesn't sound like the fans are coming on either, not sure if that's because it's cold out right now and I'm at idle.

(The day after I changed my thermo, I went to test it again to see if I was getting anything through the bleed valve and my heat was working, not as hot as before but decently hot. Still, not a thing coming from that bleeder valve though. That's really worrying me)

Any idea's? Would it be safe to pull the thermostat out, jump the fans and drive home for the holidays?(45min drive)

 

so it is still overheating? if there is no leaks anywhere then it could possibly be headgasket. does your coolant level ever go down?

 

Pressure test first. Maybe you're leaking just a bit from your newly installed water pump. A hot leak can be hard to trace. No fans tells me the coolant isn't getting hot enough to turn on your t-stat. Or your original suspicion of a clog in your radiator maybe correct. But I'd bet you'll find a leak with the pressure test.

 

I replied to your thread on G2ic man lol. Didn't u say that the lower radiator hose was cold after driving it too?

 

Yea the lower radiator hose is coldish. It's hard to tell, I know it's cold but I can't tell if it's getting warm haha, it hasn't been passed 25degrees out since this happened.

I flushed the radiator today, seems like it's flowing through the bottom hose better. But still nothing coming out of the bleeder valve. Unless that valve is clogged. I put fresh 50/50 in again. It took a while for the car to warm up to operating temp, it's really cold out right now so it's hard to tell what's going on. I'm going to try to take it to my next exam tomorrow morning, the plows keep pushing snow into my driveway so I can't go for a test yet. It will sit at idle and be fine, even reving it up won't make it go into overheat. So I'm not too sure if it's going to continue when I'm driving.

 

the weather sucks to be messing with coolant.

to test if your radiator is clogged, i put a garden hose in the filler hole. how quickly does it come out the drain hole? is it clear water?

i had random overheat issues a few years ago. i had a hairline crack in the top of the radiator plastic that was allowing my coolant to boil out.

 

I'm not completely sure why but I took it out to my exam today and the heat was hot and it didn't overheat. I'm probably going to replace the radiator as soon as possible though, I'm not sure how old it actually is. The lower hose did feel warm, not hot when i got back.