Ok guys here's my dilema. My car is running pretty hot. Above halfway on the gauge, and it's starts getting hot when I sit in traffic, but then goes back down a little when I'm driving. I jumped the fan, and it turns on right away. Now also I've noticed that when the temp gets about 3/4 of the way up, then the fan kicks in..?? Isn't that too late? Or maybe the thermostat is not openning up like it should and causing it to overheat?? I'm not sure what the problem is, but when it gets pretty hot the coolant overflows and gets spilled out. Help me out guys.
Also here's my setup. I have a 95 Sohc Vtec in my 90 civic hb.

 

well iwould say bad thermostat is what it most likely is. the best way to test the fan is let your car completly cool off then start it and let it idle to see if the fan kicks in. if it does kick in after the car warms up a little bit thenit isn't the fan. more than likely your thermostat.

 

Well the fan does kick in, but after about 3/4 of the way up. Also what sends the signal to the fan to kick in??

 

ok the water temp cuases the fan to kick in, you might have a bad sensor or as rioninja said your guage could be off

 

Where is the sensor on the 95vtec motor? and what do you mean by, my gauge being off?

 

as in the temp guage, and i don't really know about wher it is located hit um ben (rioninja)

 

When should the fan come on?? Half way on the gauge? 3/4??

 

the fan should kick in when that gauge reads about 1/3.

 

Ok, well first I'm going to change the thermo, and if it still does the same thing. Then I'll look at the sensor. Thanks for the info guys.

 

ey VTECHatch! have you fix your problem yet? I'm haveing the same problem too! I'm guessing, it could be the thermal switch for the fan to kick in.. hmmm I'll try to look it up on my chilton manual!

 

Well It stopped doing it. There wasn't enough coolant in the system. I made sure it was full, and now it kicks in when it's supposed to. It kicks in about 1/3 of the way up before even reaching half way. The other problem I noticed was that the coolant was leaking out of the overflow tube. I don't have the reservoir anymore and the tube was facing downward making the water just flow out slowly. My last thing was the radiator cap. It was in pretty bad shape so I replaced that. So far it's running like it's supposed to without overheating or kicking in too late. I started with the cheapest stuff first. Since someone here told me that it the coolant doesn't reach the sensor then the fan won't be able to kick in. I say try this first and see what happens.
Later

 

Just in case...

There are three different sensors in the cooling system. The ECT Switch (Engine Coolant Temperature Switch) is the one that tells the fan to go on. If you find the problem persists, it's a simple replacement. I think the switch is less than $15 at dealers.

-Tom

 

get a puke tank!

Everytime your car cools down, it is sucking air BACK into the motor. You'll start having problems again in about 10-15 cycles.

 

I wired my fan to come on when the car does.......hehe