The coolant in my car looks rusty and it is starting to overheat. What could be the cause?

Question

chevrolet lumina 1997

Answer 1

When you say coolant i presume it involves water plus a ethyl glycol that is usually green. The Ethyl Glycol probably expired as these would usually last 3-5 years and in my experience the rust color would tell me its time to change the glycol, flush out the coolant and replace the water plus the ethyl glycol. For the overheat you would consider the defective thermostat, blocked radiator or leak in the rubber radaitor hoses.  

Answer 2

flush the radiator  .also  look for  little puddles of liquid  behind thepass.  side tire  in the morning.that means water pump

Answer 3

Yea , I think for sure to change the coolant , this is real simple , and also check the things you were told , like the hoses and pump , but look for a leak first , it could also be small pin holes in the radiator , you would be so lucky if this is it , coz you can just add a tblesp of Black pepper and it will be fixed ,! yea , for real  

Answer 4

12 Year Old Cooling System. Boil/Flush out the Cooling System, Replace the Thermostat the could be starting to stick, Sounds like your radiator hoses might be starting to Break up/Come Apart Inside. Replacing the "Hot water Control Valve" for the heater might be called for also, Could also be Rusting. "Coolant" (50-50 Mixture of Clean water & Anti-Freeze used "All Year Round".

Answer 5

Your car came with Dexcool anti freeze from GM. It is red when new and it looks like rust when it breaks down. If your cooling system was ever topped off with green anti freeze it is not compatible and the dexcool turns to gel and plugs up everything.

The result is a radiator that cannot flow very free and probably a heater core that is near plugged off. The old dexcool also wreaks havoc with water pump seals and coolant O rings. The decreased flow and probable leakage is the reason for your overheating.

The best thing to do is get the dexcool out before this happens but it is probably too late for that in your case.

I would remove the thermostat and flush the block as well as you can, replace the water pump and flush the radiator. Then refill with distilled water only and drive it a couple days (running the heater a little each day) then flush the distilled water out with a hose. Do this 3 or 4 times with straight water & no thermostat, then put a new thermostat in and refill with a 50/50 mix of green anti freeze and water.

Cross your fingers and hope for the best, your radiator either will flow enough to cool or not. If not you will need a new radiator.

When you get to the stage where you put the new thermostat in make sure you buy a 180 degree thermostat instead of the stock 195. It will help your restricted cooling system reach full flow sooner. A bottle of Bars Leak conditioner at the final refill will help keep the water pump lubed and help the O rings to seal up again, follow the instructions on the Bars Leak bottle.

Sorry about the bad news, Good Luck!