1994 Accord - Normal Operating Temp / Overheating?

I just inherited a 1994 Accord. It’s had the water pump and radiator fan motor replaced recently.

Driving around town, the normal operating temperature is under 1/2 and above 1/3 on the temperature gauge.

I recently drove up a pretty steep 2 mile hill. The temperature never changed, but when I got to the top of the hill and parked, the fan kicked on after I turn off the car, then shortly after, coolant started leaking from the overflow tank. I estimate about 8-12 ounces leaked out.

Anyone have ideas?



This can be expected. After a hard pull the engine has a lot a hot metal to get cooled down, i.e. exhaust manifold, pistons, valves head, etc. When you shut off the engine, coolant circulation stops and there is little air exchange under the hood. On Hondas the radiator fan will come on when the radiator tank gets above the tripping point. If there is enough heat in the head and engine block to dissipate, the coolant in the block may boil, overpressuring the system and blowing coolant into the reservoir. If the reservoir overfills, coolant will spill out. The coolant remaining in the reservoir will be returned to the cooling system when the steam bubbles condense and a vacuum is produced.

One way to forstall this happening again is to idle the engine a little before shutting it off. If the fan is already on, let the engine idle until the fan shuts off before shutting the engine off.

Fill the radiator with coolant. fill the overflow bottle only 1/2 full. Change the radiator cap. The cap seal may be bad.

Thanks to both Researcher and Hellokit for the replies. You should stand in as substitute Cartalk hosts…


Check the radiator from the rear with the shroud tilted back. If your fins between the tubes are rusted away (about 5% of them gone or more) it is time for a new radiator too. If you see white or green on the radiator, it is a bad sign.