Today driving home (40 minute commute, hurrah), I look down and my engine heat is up at the red. Crap.
I pull over, as soon as I can, strategically next to a place where this group of guys buys crap cars and fixes them up.
One comes out, we talk briefly, asks me if my coolant level is low (I haven't checked recently).
Tells me to turn the car on to see if the radiator fans run, they don't.
He grabs a wire, connects it to one of the fans wires then to the batter, fan runs, engine cools and stay cools for the remainder of the 10 minute drive.

I'll get pictures of the fix soon so you can see where he connected the wire.

What could this be? Thermostat for the fans broken? Wiring gone bad? I don't think there was any fluid being moved around, the tubes were quite warm and smoke was coming out of the overflow reservoir.

and I still haven't checked the coolant level, still too hot.

Oh, edit, 95 civic lx manual tranny

2nd edit: I just checked, radiator is bone dry. I'm about to refill it, so that answers one question.
The other question is, why wouldn't the fans turn on while the engine was on, no started, just on? Would they not run because there was nothing to even tell sensors to turn on or?
And I just saw another thread minutes about about an 84 or 86 car, I overlooked it while searching for radiator/cooling related issues.
Don't flame me, just simply overlooked it.

 

the temperature sensor bases its reading off of the temperature of the coolant. If there was absolutely no coolant running through the thermostat, then the reading would be very inaccurate if it is able to take a reading at all. and even if it does read that its hot, without coolant theres nothing that the engine can do to cool it off.

so start by filling up the radiator and the reservoir and see if it still overheats.

 

agreed, same thing happened to mine, although being that there was no coolant in my civic it was unable to get a reading at all so it just stayed in the normal range, even though it was overheating, i blew a headgasket. So like he said, replace coolant see if fans come on at all, if not fan switch maybe

 

Ok replaced my coolant. I decided there's nothing wrong with the radiator fans...they didn't turn on because they simply didn't need to be turned on. The coolant wasn't getting hot enough to need to be cooled down.

Then my next question is...for me to lose coolant, an entire "tank" worth, I probably have a leak.
What're some major spots where leaks happen? I know the first thing to check would probably be hoses and the drainage plug (?), but any other obscure places or surefire ways to tell where it's coming from?

Thanks for the help fellas. THat's why I -love- this forum

 

well when was the last time you changed the coolant before this time?

 

It can be a chicken and egg situation with the coolant level. If the engine overheats and you don't notice right away, the coolant will boil out.

I would suggest replacing the thermostat, they can get sticky and cause sudden overheating when they stick closed, even though you have normal operation most of the time. After doing that fill the sytem and purge it completely, then let the engine idle until the fan comes on to show that it works. Watch the temperature gauge closely during this test.

On a 95 only the single fan on the radiator is needed to cool the engine. The other fan on the A/C condenser on the drivers side is used only for A/C, it has no effect on engine temperature.