Hi all, first post! I have a 1996 Honda Accord, I have noticed that after driving a couple of miles and I turn the engine off, the fans come on and run for a couple of seconds. This repeats as when the engine is running. This is the first time I am the owner of a Honda so I don't know if it is normal or sme wiring change that was made before my purchase. Any ideas??

 

Your description sounds normal to me.

Hondas have two sensors that operate the cooling fans. One works when the car is running and the other works when the car is turned off. Your description is normal for an Accord. My fans usually turn on for a minute or two after I shut off the car in warm/hot weather.

 

as long as they stop after a little bit and shut off on their own I'd say it sounds pretty normal...

 

Good, I glad we cleared that up! Now on to the real problem. I recently replaced the radiator, because the top broke off where the hose connects. Since having this job done, I have noticed that the fan takes a longer time to come on and when it does, it is just for about 5 secs. It no longer comes on when I turn the engine off. I should note that I live in a very hot humid island in the caribbean. I aslo removed the termostat, since the car started to throwa lot of water into the overflow after a long run. I removed the top hose and kept the engine running and the water was just barely trickling out, mechanic said it was stuck.

 

So your car has no thermostat right now? Was your car overheating when your removed it?

Without a thermostat your engine will take a long time to warm up, because the engine has to heat up all of the coolant. Your engine will run rich and waste gas. The thermostat is designed to open up as the coolant gets hot in the engine.

Replace with a thermostat from Honda asap, do not use an aftermarket one on this job. Its a $15 part and easy to do.

The radiator might have been partially clogged causing less antifreeze to cool down, and the fans had to come on after the car was turned off. I noticed the same thing when I replaced my radiator. I flushed the system with commercial cleaner and then replaced the old thermostat.

 

No, I do not have a termostst on at this time. And Yes, it was overheating, while the guage did not cross the midway mark, when I turned the engine off, the water from the radiator was feeding into the overflow tank and boiling over. Trinidad is a very hot place, without the termostat I can get my temperature to reach normal driving temperature in less than 3 minutes of normal driving at 6:00 am in the morning. We do not use anti freeze here due to the tropical weather, however we do use coolant, and this I have failed to replace. Can this be the cause of the fans not coming on?

 

That can definitely be the cause of the fans not coming on. You temperature sensors seem to be working, because the fans still turn on when the car is on and turned off.

The thermostat is in there to keep the coolant at optimal temperature for engine preformance (fuel efficency, etc.). When the car is at normal operating temperature, the thermostat should open yet still control internal engine coolant temperature.

If this was my car, I would install a new thermostat. As long as your engine doesn't overheat, I can't think of any engine damage being done without one.

When you say you use coolant, do you use only water or do you use somethingelse in tropical climates?

EDIT: I agree with the comment below, so I edited that sentence.

 

I don't agree with that. When the engine is at normal operating temperature, the thermostat is constantly adjusting itself to maintain proper temperature. If it were staying wide open, it would overcool in most cases.

 

The thing is, the thermostat is not in an dthe temperature is just about 1 stroke (the width of the temp guage needle) below the midway mark. It is certainly not over cooling. However as I said before, the fans no longer run when the engine is turned off after along run. Today I am draining the water and replacing it with 2 gals of coolant and top up with water.