First, let me say that I am new to this and cars are not my area of expertise. Having said that, I installed a new radiator in my 2000 Honda Accord 4 cylinder. I replaced upper and lower hoses, new clamps and added new antifreeze 50/50. Except for a little transmission fluid leaking afterwards, everything seemed to have gone well.

Now my radiator seems to get extremely hot and the cooling fans don't turn on (often) while idling. When they do come on it is not long enough for them to cool anything. The fans do come on when heater/ac is turned on. Car doesn't overheat and temperature gauge appears normal. Upper hose gets extremely hot and lower hose slightly less hot.

One thing I did not do is trim the upper hose when I installed the radiator. It seems to be slightly crimped. Could this be causing a problem which would cause the fans not to work correctly? Or maybe a thermostat issue? Any help appreciated.

 

Might have some air stuck in the system, did you bleed it. You should trim the hose for a correct fit regardless. Did you change the thermostat?

I would start by just bleeding the system out and trimming the hose and double check after that...it sounds like you'll be ok, if the gage is reading like it always has, i wouldn't worry too much. The fan cycle will be fairly short when it's just sitting at idle.

 

No, I didn't replace the thermostat yet, and I wasn't sure how to bleed it. I ran it for a little while with the rad cap off and thought that would do the trick. Is there a bleeder valve to open up? I will trim the hose as well.

 

Yes, the bleeder screw is in the thermostat housing. When the engine is cold, remove the rad cap and open the bleed screw. Add coolant until it flows in a steady stream out of the bleeder...close the bleeder. Leave the cap off and start the engine and run until the fans come on, top off coolant if necessary and replace cap.

 

There is a good ericthecarguy video on bleeding the coolant on YouTube. Just do a google search and you will find it.