I got a 91 civic hb with a problem. When i hit 35 mph my temp gauge goes above the redline. Friend of mine told me to swap out thermastats. but i still have the problem.......any ideas??

 

anyone??

 

Hi,
You already changed the thermostat, so the next thing would be to do a cooling system flush. This is cheap to do but time consuming. It will remove the crud in the radiator that acts like insulation preventing the inrushing cool air from cooling the water down. One time i had to remove the ac radiator because it was so clogged with debris and prevented airflow to the radiator cooling the engine, hope this helps!

 

what do i need to do that.....and I dont' have an A\C in my civic would be nice

 

i mean can i go to autozone or someplace and tell them i am doing a cooling system flush and they will hook me up with what i need.....I am new at this stuff, computers are my speciality

 

No problem,
It's coolant flush that you need. About 5 bucks. Drain out the old stuff, there should be a plastic hand turnable screw under radiator (passenger side usually). Recap and pour entire bottle in and top with water. Go driving for 15 minutes to oscillate and shake the corrosion off the walls. Park, let cool. Drain again. Refill with water only, drive 15 minutes again. Cool and drain. The the third time you just refill with water and coolant. Should do the trick.
The corrosion is caused by minerals from the water, and you should used distilled water in a perfect world. But a routine flush is good.

 

alright i wil give that a try..all the stores are closed now so i will try tomorrow..i will let you know what happens..thanks

 

Does the coolant look milky? Does the temp. shoot to redline quickly, or just slowly move up?

Are your fans coming on? Does it happen when the car idles, or only when you are moving forward? Water pump spinning/working (belts stuff like that)?

Doesnt sound to me like a coolant flush is gonna fix it... Check these things and then we can move on from there.

 

Yea, thats right... check your fuses to see if the radiator fan has a blown fuse. It will happen because the fan load is subject to surges of current.

 

well i had a friend of mine come over...and we did a complete cooling flush..and so far so good..hasn't raised above half...and i drove it hard on the bypass just to make sure.....Thanks Alot

 

Kool,
sounds like that may have been a factor. still good to check everything though. Get a Hanes manual, and learn the maintenence procedures.