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Question:

How Do You Identify a Bad Water Pump?

My 2000 Pontiac Sunfire has been overheating and I recently changed the thermostat thinking that was the problem. The new thermostat didn't help and the engine is still over heating. I am starting to think it might be the water pump. How can I tell for sure? When I changed the thermostat and refilled the coolant tank I left the cap off and started the car to work out the air. I was told I should see bubbles in the tank but nothing happened, I thought this might be a sign of a bad water pump. I think I will be able to change the water pump on my own I just want to know for sure if that is the problem.

Answer:

It could ALSO be crud build up in the radiator interior or road junk in the radiator fins. A bad water pump USUALLY leaks and/or squeals
Step 1 Open the car hood and locate the thermostat on the top of the radiator lid. Pull the thermostat and start the car. Watch the temperature gauge carefully. If the water pump is working properly, the engine should take a long time to warm up (if it ever does). With the thermostat removed, the coolant should circulate continuously, making it harder for the engine to warm up. If you cannot tell if the car is heating up slow or not, move to Step 2. Step 2 Turn the car off and locate the water pump and the water pump drive belt in the engine compartment. Use the wrench set to loosen the belt retaining bolt and pull the belt off of the pump. Spin the belt drive with your hands to see if it rolls smoothly and to determine if there is any movement or play in the driveshaft. If the pump seems in good working order, replace the belt, tighten the retaining screw back up, and move on to Step 3. Step 3 Locate the coolant drain plug on the bottom of the radiator and use the wrench set to remove it. Allow all of the coolant to drain out into a container and dispose of it. Replace the drain plug in the bottom of the radiator and then pour coolant into the radiator. Start the car up and watch the level of coolant carefully. If the water pump is working properly, the coolant level should drop quickly as the pump circulates coolant to other areas of the engine. Fill the radiator back up with coolant and watch it to drop again. If the coolant drops then your water pump is fine, however if the coolant drops very slowly or not at all it may be time for a new pump.
I agree with f100-supersabre's answer. And here's some more to ponder... Chances are your water pump is just fine. When was the last time, if ever, you serviced your cooling system? And by that I mean dumping the old anti-freeze, back flushing the system to include the heater core and refilling with fresh coolant. If the answer is never then your radiator is probably toast. The internal passages are clogged and it does not dissipate heat effectively any more. Another thing to consider: the electric cooling fan(s). How many does your car have? With one fan, the fan will run: Anytime the A/C is switched on. When the tempurature sensor in the cooling system rises above the preset value of the sensor. With two fans: One will only and always operate when the A/C is switched on. The second will operate in response to the preset value of the cooling system sensor. Check the operation of the fan or fans. Turn on the A/C, the fan or one of the fans will turn on. With one fan only, turn the A/C off and let the car idle until the the single fan turns on in response to engine temperature. With two fans, you can let the A/C run and let the car idle until the second fan turns on in response to engine temp. If the fans don't work as they should, the first place to look is for a blown fuse. High amp fuses are found in the engine bay in a seperate fuse box ...look for this ..pop the lid and check the fuses. A map for the fuse purpose/location is usually found under the lid. If the fuses look okay, then it may be a bad sensor or it might be a bad fan. The sensor is usually less expensive and easier to swap out than the fan assemblies. Your cooling system, if has been neglected, may need both a radiator and some work on the fans if they prove less than up to snuff.
bubles would be a bad thing commmon issue with the cavalier and sunfire is blown head gasket and they overheat big bubbles coming up in the tank is the sign of a blown head gasket and they always overheat then if no bubbles then thermostat is usually whats wrong in these cars. makre sure you bleed the air out of the black steel tube in front of the engine there is a bleeder screw on it also makre sure the cooling fan and relay work by unplugging the CTS sensor on the driver side end of the head, black oval shaped two wire plug takes a few seconds to kick on
It's an anaerobic micro organism (that's, it does not want oxygen to outlive). I had this situation, and that is what I did: Remove your good cap and pour in a cup of Clorox combined with a part cup of baking soda. Run the water for 10 mins by way of all of the areas it comes out, sinks, bathrooms, washing desktop, dishwasher, bathe. This will disperse the bleach by way of the method and kill the micro organism. You should not drink the water except you run it by way of a Brita or different filter out, or you'll use bottled water for a few days. After a few days of utilization, you should not be capable to sniff the chlorine and the water might be riskless to drink once more. You would possibly need to do that as soon as a month, even though you may also now not have got to use such a lot Clorox.

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