How to test for a bad water pump?
#1
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I've been having a problem with the fans running after engine shutoff. Usually, when in stop and go driving. Hasn't done it in a while because it has been in the 20s and 30s here in Dallas. But got up to the upper 50s yesterday. And fans running once I got home, lot of stop and go traffic.
Thermostat I replaced it October of 2017. Heater works great, so I believe thermostat is working fine.
Water pump does not leak. I have no coolant leaks. Never have been able to get a coolant reading off torque pro, that is annoying. Coolant gauge doesn't go past 1/2, but I know they aren't accurate.
So how do I test for a bad water pump? It was replaced(based on service records) in 2013. But I don't know if it was replaced with the plastic, or metal impeller pump.
Thermostat I replaced it October of 2017. Heater works great, so I believe thermostat is working fine.
Water pump does not leak. I have no coolant leaks. Never have been able to get a coolant reading off torque pro, that is annoying. Coolant gauge doesn't go past 1/2, but I know they aren't accurate.
So how do I test for a bad water pump? It was replaced(based on service records) in 2013. But I don't know if it was replaced with the plastic, or metal impeller pump.
#2
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Didn't know that about the impeller, thanks. I know it is ok for the fans to be on in traffic. But not ok for them to run once I turn the engine off.
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(I was responding when Jim was and thus duplicate info...hint, hint)
Its ok for the fans to run after you shut the motor off, though its an indicator. The issue is you would know you had a overheating problem because the fans are supposed to keep the system at a constant regulated temp during operation. Understand that the fan relay is just like a light switch only temp regulated. When it reaches a specified temp, it connects a power relay for the fan...and as long as that temp is activating it, the fans will flow until that temp comes down, barring a bad/sticking switch.
The cause of that, 99% of the time is lack of flow. It could be restricted/clogged radiator cores (poor maintenance or that Stop Leak crap), ...thermostat not opening (simple failure), the water pump (part failure, ...bearing, impeller) or blockage in a non moving part of the system (passages in the heads/block). And/or a combination of any of the prior.
I always start with the simplest and cheapest...fluid check first, then a combination thereof since they all are easiest done at the same time with the fluid out. Radiator flush if it tests inadequate, then thermostat, switch and any weak hoses.
Its ok for the fans to run after you shut the motor off, though its an indicator. The issue is you would know you had a overheating problem because the fans are supposed to keep the system at a constant regulated temp during operation. Understand that the fan relay is just like a light switch only temp regulated. When it reaches a specified temp, it connects a power relay for the fan...and as long as that temp is activating it, the fans will flow until that temp comes down, barring a bad/sticking switch.
The cause of that, 99% of the time is lack of flow. It could be restricted/clogged radiator cores (poor maintenance or that Stop Leak crap), ...thermostat not opening (simple failure), the water pump (part failure, ...bearing, impeller) or blockage in a non moving part of the system (passages in the heads/block). And/or a combination of any of the prior.
I always start with the simplest and cheapest...fluid check first, then a combination thereof since they all are easiest done at the same time with the fluid out. Radiator flush if it tests inadequate, then thermostat, switch and any weak hoses.
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#7
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Coolant level is 100% correct. I was fixing a small leak a few days ago. And when I drained the coolant, it flowed smoothly and fast. Came out clean as well. Very clean in fact. Does that indicate the system is clog free? Thermostat is a 3 month old Stant.
So basically, if water pump isn't leaking, the water pump is fine? Sorry for the novice questions.
So basically, if water pump isn't leaking, the water pump is fine? Sorry for the novice questions.
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#8
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No, it just means your drain point is clear. You need to get an anti-freeze tester, ...the ones with the little ***** in them. A radiator shop may be able to put a bore scope in and check for blockages on the cores.
Your pump can still be bad. The only reason they leak is because of wear on the bearing. If your bearing is good, but your blades are spinning free or broken off, you will only know by taking it off. But, like RJ said, the impellers were pretty well corrected by 2013.
Have you done a compression check Brandon? If you have a head gasket issue, that will cause overheating. Be sure to check your plugs as you take them out, you'll see a big variance in residue if you have one cylinder blowing into the other.
Your pump can still be bad. The only reason they leak is because of wear on the bearing. If your bearing is good, but your blades are spinning free or broken off, you will only know by taking it off. But, like RJ said, the impellers were pretty well corrected by 2013.
Have you done a compression check Brandon? If you have a head gasket issue, that will cause overheating. Be sure to check your plugs as you take them out, you'll see a big variance in residue if you have one cylinder blowing into the other.
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No, it just means your drain point is clear. You need to get an anti-freeze tester, ...the ones with the little ***** in them. A radiator shop may be able to put a bore scope in and check for blockages on the cores.
Your pump can still be bad. The only reason they leak is because of wear on the bearing. If your bearing is good, but your blades are spinning free or broken off, you will only know by taking it off. But, like RJ said, the impellers were pretty well corrected by 2013.
Have you done a compression check Brandon? If you have a head gasket issue, that will cause overheating. Be sure to check your plugs as you take them out, you'll see a big variance in residue if you have one cylinder blowing into the other.
Your pump can still be bad. The only reason they leak is because of wear on the bearing. If your bearing is good, but your blades are spinning free or broken off, you will only know by taking it off. But, like RJ said, the impellers were pretty well corrected by 2013.
Have you done a compression check Brandon? If you have a head gasket issue, that will cause overheating. Be sure to check your plugs as you take them out, you'll see a big variance in residue if you have one cylinder blowing into the other.
Supposedly it was thoroughly flushed when the water pump was changed. Who knows. I will still check that.
I have a video of a cold start this morning, and was watching the coolant circulation to see if the pump was doing its job. Would you guys like me to upload it?
Have not done a compression check. I can pull the plugs, seems pretty easy on this car. Should I start with pulling the plugs first?
#10
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You can connect a scanner with livedata to the OBD port and monitor the ECT temp reading after some driving once you get parked, it will show you the exact temp reading. The dash temp needle isn't very accurate, it's a nonlinear reading so it's got a pretty wide range where it is in the middle position.
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#12
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You can connect a scanner with livedata to the OBD port and monitor the ECT temp reading after some driving once you get parked, it will show you the exact temp reading. The dash temp needle isn't very accurate, it's a nonlinear reading so it's got a pretty wide range where it is in the middle position.
+1 to nilanium's suggestion....
Checking the plugs is easy and can be done in about 30-45 minutes roughly. But if your going to check the plugs, you may as well do a compression check.
True. I know a bad head gasket doesn't have to have mily oil. But my oil isn't milky.
If you want, you can load the video, couldn't hurt.
Checking the plugs is easy and can be done in about 30-45 minutes roughly. But if your going to check the plugs, you may as well do a compression check.
True. I know a bad head gasket doesn't have to have mily oil. But my oil isn't milky.
If you want, you can load the video, couldn't hurt.
Will upload the vid shortly.
#13
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My 97 always ran the fans for 10-15 sec. after shutdown if it was at operating temp, even if the fans weren't running before shutdown.. I suspect it was programed in the ECU.
A plastic vane impeller can fail, but it's very rare, and doesn't necessarily result in a leak, which is usually due to a seal/bearing failure.
A plastic vane impeller can fail, but it's very rare, and doesn't necessarily result in a leak, which is usually due to a seal/bearing failure.
#15
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My 97 always ran the fans for 10-15 sec. after shutdown if it was at operating temp, even if the fans weren't running before shutdown.. I suspect it was programed in the ECU.
A plastic vane impeller can fail, but it's very rare, and doesn't necessarily result in a leak, which is usually due to a seal/bearing failure.
A plastic vane impeller can fail, but it's very rare, and doesn't necessarily result in a leak, which is usually due to a seal/bearing failure.
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#17
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I got the same flow and bubbles in my reservoir, and I am sure I have no issues.
I dare to say it is the coolant flow moving around, which then also indicates your waterpump is functioning.
Don't think so.
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#19
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Five minute fan run off is way too long. Bubbles should go away after a while if it is trapped air (some folks "burp" the system) or loosen the cap on top of the thermostat housing: I never had to do either. After letting it warm up (hoses are now hot and thermostat is open), the trapped air would bleed out at the reservoir after a few minutes.
Thus +2, get a compression check or cooling system pressure check to test for a bad head gasket. I have to think about the utility of a pressure check with this system since it has that overflow tank in the fender.
Thus +2, get a compression check or cooling system pressure check to test for a bad head gasket. I have to think about the utility of a pressure check with this system since it has that overflow tank in the fender.