I have a 1997 Honda Prelude SH and it overheats. I just replace the thermostat but it still overheats. The gauge goes about 80% up and after a while then the fan kicks in and the gauge drops back to the middle. What else can be the problem?

 

What were the specs of the thermostat anyway?

Make sure you didn't put it on backwards........

also, make sure your coolant:water is 50:50

Also, make sure your cap is holding pressure - the higher the pressure, the higher the boiling point.........

all i can think of right now. Just pulling **** out my ***.

 

you could also have a blown head gasket that causes overheating, but i would start with the cheaper things first. like change your coolant, make sure there is no build up in the houses. if everything else is fine it could be the head gasket

 

the thermostat is brand new and is oem. i am pretty sure i install it in right. pretty simple. it overheated with the old one too and i thought that was the problem. the coolant is already premix at 50/50. and the cap im pretty sure is not the problem.

 

i just replace the head gasket. less then 5,000 miles on it. so that not the problem. could it be coolant temp sensor?

 

yeah thats what i was gonna say. could be that the sensor is not reading the temp correctly, and is causing the fan to come on late. just swap it out. costs like 15 bucks, and its mounted right in the thermostat housing. let us know how that works.

 

i will give it a try. I'll go to honda and get the parts order today and let you know how it turns out. thanks

 

take off the radiator cap and turn the car on, if it bubbles for a while and then stops then there may have just been air in the system, if it keeps bubbling for a looooong time even after reaching normal operating temp then the headgasket may be blown/installed incorrectly, if upper radiator hose is not getting warm then thermostat is still messed up (since it overheated again u will probably need another thermostat, overheat them once and quite often the dont work correctly anymore), if the upper rad hose gets hot and the temp needle/bars get to halfway between c and h or higher and the fans have not come on yet then its thermo switch, if the fans dont come at all try turning on the a/c, once the a/c is turned on both fans should turn on immediately, if one or both dont then theres something wrong with the fans, i think thats just about everything related to engine overheating....also check the oil for coolant and coolant for oil as a sign of headgasket leak

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by twistedbydezign &raquo;</TD></TR><TR><TD CLASS="quote">take off the radiator cap and turn the car on, if it bubbles for a while and then stops then there may have just been air in the system, if it keeps bubbling for a looooong time even after reaching normal operating temp then the headgasket may be blown/installed incorrectly, if upper radiator hose is not getting warm then thermostat is still messed up (since it overheated again u will probably need another thermostat, overheat them once and quite often the dont work correctly anymore), if the upper rad hose gets hot and the temp needle/bars get to halfway between c and h or higher and the fans have not come on yet then its thermo switch, if the fans dont come at all try turning on the a/c, once the a/c is turned on both fans should turn on immediately, if one or both dont then theres something wrong with the fans, i think thats just about everything related to engine overheating....also check the oil for coolant and coolant for oil as a sign of headgasket leak</TD></TR></TABLE>

Good info! thanks

 

Water pump? Can the really go bad (stop pumping) or do they just leak.