Why is my car overheating on high rev. ie, on high acceleration or climbing steep hills?

Question

The car is a 1997 honda accord SiR made in Japan, there is no radiator nor water leaks,thermostat was removed by dealers, and cooling fans working fine.

Answer 1

No loss of water in sealed system? Cannot be blown head gasket, leaks, etc.

Recheck thermostat as I agree that a dealer would not just remove it. And they have been known to install the wrong one(all the thermostat does is allow coolant/water in engine to reach operating temperatures quickly). Simply a valve that opens when hot.

Coolant at proper ratio- somewhere at 50/50??? NOT using coolant can cause this problem(but it's for freezing right?- WRONG primarily used to lower boiling point!)

Last look at your hoses(intake/outtake) for radiator. Keep hands off(moving parts and I'm sure you're attached to your body parts)
and at higher rpms... see if the intake hose to radiator is flexing together(squashing). If the hose squashes on the outtake from radiator then your radiator is plugged up. If it is squashing(or if the hoses are more than three years old) REPLACE them(don't forget the heater core/radiator(and some hoses need a metal spring insert to help them remain round- yours may be missing).

Lastly when overheating run your heater at full blast(YES I know BUT that acts as an auxiliary radiator using the heater core system- windows open AC off.

And when flushing system run heater to flush that part too. After hose replacement(four hoses) and new DISTILLED water/ coolant replacement run engine till warm with heater ON to ensure you've filled to operating line at reserve reservoir(at that point radiator cap back on or as it heats it will flow out radiator and not back to reservoir), OF COURSE never remove radiator cap while under pressure(HOT). As a habit I always place a large cloth over cap area SO if it sprays it hits cloth and NOT face!

And last but not least your water pump may be shot or not being driven by belt... but I doubt it. Shot ones usually leak BUT I have seen where belts were replaced missing the pulley on the water pump- once.

Answer 2

If the thermostat was REMOVED, then the car would not be overheating. It would take a long time to warm up.
Like many above: check your radiator fluid level and quality. It may be best to just drain the system and refill with 50/50 antifreeze water. Having it flushed would accomplish both. Inspect your radiator for damage and "crud" blocking the fins. I believe Hondas use a fan to aid airflow over the radiator when temp get high. You'll probably have to have a mechanic check to see if that is working. Hope this helps.

Answer 3

Jon, That is an interesting question. I see you received some comical answers. Surprisingly your Accord engine may rev to 6250 without any damage whatsoever. I don't know how many miles are on it, or if it is making any noise right now. That is really irrelevant. The reason some engines are "red-lined" or governed at a certain speed is because of the accessories. Things such as the alternator or power steering pump may do strange things at higher RPMs. Belts tend to come off and pulleys tend to come apart at higher RPMs. This could get pretty ugly when pulleys start coming apart. I won't even get into flywheels or clutches at such high RPMs. You get the idea. If the engine were removed from the car and mounted to a stand, the engine may be capable of turning 10,000 RPM without any problem.

Answer 4

Well I will tell you this from an old man lol. If you circulate the water to fast in system it will not cool your engine. Found this out hard way lol took a thermostat out of an old tractor and it ran hot all the time till i replace the one item that slowed down the the water flow so it could be cooled lol.
Under high rpms you may be circulating the water to fast to cool it down. Put a low temp thermostat back in it see how that works out lol.

Answer 5

IF THE THERMOSTAT HAS BEEN REMOVED TOTALLY . THAT CAN BE PART OF THE PROBLEM . THE THERMOSTAT HOLDS THE WATER IN DIFFERENT AREAS TO ALLOW FOR COOLING TIME BEFORE LETTING THE WATER BACK INTO THE ENGINE BLOCK. YOU COULD HAVE A PLUGGED UP RADIATOR. WATER PUMP COULD BE GOING OUT . I CHEMICALS SUCH AS ANTI-FREEZE 50/50 MIXTURE .MAKE SURE THE CHEMICALS ARE NOT TO OLD . HEAD GASKET CAUSES HIGH TEMPS AS WELL . BUT THE SIGNS OF THAT WILL BE WHITE SMOKE COMING OUT OF YOUR TAILPIPE . VERY WET FEELING TO THE TOUCH. CHECK ENGINE OIL FOR PROPER LEVELS AND COLOR. IF YOU PULL THE STICK OUT AND IT IS A YELLOW COLORED OIL ON THE STICK . YOU MAY HAVE A LEAKEY HEAD GASKET INSIDE THE BLOCK. FREEZE PLUGS ALSO GO BAD. CHECK FOR LEAKS.LAST BUT NOT LEAST. SMALLER CARS HAVE A HARDER TIME CLIMBING HILLS BECAUSE OF THE SIZE OF THE ENGINE ..... IT IS BETTER FOR SMALLER ENGINE CARS TO TURN OFF THE A/C WHEN CLIMBING. THE HARDER YOU PUSH ON THE GAS PEDAL THE MORE FUEL YOU PUT INTO THE CLYINDERS CAUSING THE ENGINE TO RUN HOTTER . THEY HAVE A PRODUCT IN THE AUTO PARTS THAT IS ADDITIVE TO TO OIL. IT TREATS THE METAL TO CAUSE LESS FRICTION..... SLICK 50 OR ANY NAME BRAND WILL HELP

Answer 6

I would run a engine flush with the theromstat out of it, but put the thermo back in after the flushing, it causes a small blockage which allows the water to be cooled properly in the radiator, without it in , it is possible that the water flow is too much, and the water cannot cool,

sounds to me like the electric cooling fan is not working or the sensor to turn on the electric fan is broke,

Answer 7

put thermostat back inor put in another honda thermostat. never run without thermostat. coolant won't stay in radiator long enough to cool properly. your dealer removed it? they should be hung by their fan belts. radiator is plugged internally. a radiator shop may be able to rod it out but honda rads have plastic caps i believe and they don't always carry sealls for the tanks so buying new radiator would be alternate option.

Answer 8

i had a similar problem with my Toyota once. but i found that it was only when pressure the car too much especially over steep hills.
i was at one point worried that there was a problem with engine head but the car was not using any liquids so that's that.
i have changed my muffler system. (using headers etc) i don't know if it was that that solved the problem but i don't have it any more
get your radiator flushed too

Answer 9

1. refill radiator 2. test water pump 3 clean water,grill spray bugs out of radiator. check compression on cylinders

Answer 10

put thermostat back in..this causes water to flow to fast and can not be cooled...also use high pressure water house and wash out radiator...and also but back front air dam under front bummer..that is used for high speed cooling...this should help ...