86 accord very hot....

[Deadhead]

OK, so i'm traveling from Loveland CO to Denver yesterday, and my car seems to get to about 7/8 up on the thermostat, but no further, while i'm in town, it doesn't go over 1/2. There is plenty of coolant in the reservoir and the radiator, I'm at a loss at what could possibly cause this. I was traveling 75 to 90 mph. So my RPM's were above 3,000 the entire time. The strange part is when i got down to rush hour, there were dead stops, and still it is very hot. Can you give me some ideas? and also walk me through the process of what could cause this excess heat. I am told that the car should never get over 1/2 way up.

thanks

[Igovert500]

Are your fans coming on? When is hte last time you replaced your thermostat?

[94hondaacc]

i would think its your thermostat not opening. you should have it changed. you might want to flush your radiator too just to make sure that doent get clogged either.

[Deadhead]

The fan's do come on, and i haven't had the car for more than 7k miles.

Could the thermostat be the cause?

[Deadhead]

http://www.autopartsworld.com/1986_h...tat_parts.html

is this the piece that i need? and is it just on the intake manifold?

[94hondaacc]

yeah that s the part. its supposed to open when the car reaches a certain temp, to allow the car to cool down, problem is after a while it might get stuck, causing the car to overheat, thats why this is most likely the problem, since the fans go on.

[Deadhead]

ok, thanks a lot.

I appreciate all the help you guys give me....

THANK YOU!

[94 Accord]

It can be the thermostat. Also is there anyway you can find out when was the last time ur water pump was changed? The bearings could possibly be worn in ur water pump.

[AccordCodger]

Worn pump bearings wont have much, if any, adverse effect on the cooling itself. They'll make a racket and probably leak all over the place instead.

[Deadhead]

Is there anything i need to do when replacing the thermostat? is it just a simple unscrew and screw on type thing?

[AccordCodger]

Bleed the cooling system after you're done.

[Deadhead]

ok, after looking at other threads... i see that when the thermostat is having a problem, it's also in Town driving. The ONLY time mine get's hot, and it doesn't even overheat, is when i am driving on the Highway. Can someone explain to me why this happens?

I just looked at my car and let it idle and again, it wouldn't go above 1/2. I also drove it around, again, no problems.

Is there a reason for it only getting hotter than normal when i'm on the highway?

[jeffcoslacker]

If the thermostat is sticking only partly open, or the radiator is hogged up with crud, there isn't enough coolant movement to keep up with the additional heat the engine is producing at higher revs. So the faster you go, the quicker and harder it'll heat up.

At idle, and lower speed, the volume of coolant moving past the restriction may be sufficient.

[jeffcoslacker]

Make sure you aren't missing a deflector underneath also. Cars now with their very small grille openings depend mostly on directed air from under the front to cool the radiator. If you knock one off, you can't get enough airflow at highway speeds.

[Deadhead]

Originally Posted by jeffcoslacker

If the thermostat is sticking only partly open, or the radiator is hogged up with crud, there isn't enough coolant movement to keep up with the additional heat the engine is producing at higher revs. So the faster you go, the quicker and harder it'll heat up.

At idle, and lower speed, the volume of coolant moving past the restriction may be sufficient.

So what your saying is that it could be my Radiator OR my thermostat.... right? If it is the Radiator, how would i tell if it's got a lot of crud in it?