[s0duva02]

I am now at 72k miles and I had a leak coming out of Water Outlet, its a black pipe that the upper coolant reservoir hose connects to. the connection to the hose blew when I touched it and boiling coolant sprayed up like a volcano almost burning my face! also the black water outlet had another leak right abovewhere the coolant returns from the radiator. This Water Outlet black pipe has about 4-6 hose connections on it with Ithink 3 or 4 bolts holding it to the side of the motor.
Needlessto say, I noticed the motor began to run hot, and that’s when I found thoseleaks. I replaced the water outlet piece and the car ran for a few miles andsaw it began to overheat again… I flushed the radiator and still sameresult. I grabbed hold of a few hosesand began feeling as the car gained heat ( my wife was in driver seat ready toshut off the motor once it began to get above ½ mark on thermostat) I noticedthe hose behind the water pump was very hot, and the hose after the water pumpwas cold .

Thefirst time at 30?k miles I replaced the water pump was because I could see itleaking from the pump. This time, thereis no leak, my guess is the motor overheating has ceased up the pump fromworking properly, so I will attempt to replace my water pump again now at 72kmiles. I am very glad I wrote up this forum so I can go back and look at mynotes from the first time!

 

[carbon02]

sOduva02-

Wait a second before replacing the pump. The large hose from the radiator to the pump will be closed when the thermostat is closed, and the car operating correctly. Therefore it should be cold.

The hoses on the backside of the pump, come from the heater core. This core is hot all the time, even if there's no command for heat.

I'm not sure exactly where you're measuring temperatures, but I think we need to think about this a little more. The small half inch connection at the back of the pump will be hot, as it's on the block side of the water pump.

All this is going from memory, but it's possible that you had a coolant to reservoir connection go bad. This part has been redesigned, and there's threads about it.

there's also threads about the water outlet being a problem.

If the pump doesn't leak, and has no noise in the bearing I think it's ok.

 

[s0duva02]

in the picture attached is the water outlet piece that I replaced showing where the 2 leaks came from, the top arrow is where the volcano geiser came from after I touched the hose! This is a general pic of the water outlet which I added the red arrows to show the leak spots, I grabbed this image off of google images.

 

[s0duva02]

thank you, I will take any advice before I go and take apart the pump again...Im not sure where the threads are that you mentioned, im still looking for them.

 

[ChevyGuy]

in the picture attached is the water outlet showing where the 2 leaks came from, the top arrow is where the volcano geiser came from after I touched the hose!

But you said you fixed that.

At this point I'm wondering if you have a bad thermostat. Until that opens, you'll get no coolant flow to the radiator - and yes, your car will overheat.

Try cranking up the heater in the car. If it cranks out the heat, then the water pump is pumping. (From what others have indicated, crank it up high enough and the engine may not overheat.)

 

[s0duva02]

But you said you fixed that.

At this point I'm wondering if you have a bad thermostat. Until that opens, you'll get no coolant flow to the radiator - and yes, your car will overheat.

Try cranking up the heater in the car. If it cranks out the heat, then the water pump is pumping. (From what others have indicated, crank it up high enough and the engine may not overheat.)

Yes I was just posting that pic to show the leak places for future cruzers with leaking water outlet... It is fixed now and so far no leaks there anymore... I have also been curious of the thermostat myself... I will try to troubleshoot if that is the issue and update this forum

 

[carbon02]

Check for air in the coolant system. I believe there's a small bleeder valve on one of the radiator tanks. Consider running the system with the cap off until you see coolant coming back to the tank from the hose connection you replaced.

 

[s0duva02]

Ok, so I'm at a standstill…I found the white plastic bleeder screw…I bled the air out until coolant was coming out…I then drove with same issues of overheating… going after the air bubble theory I began testing the Heat/Air, the heat was not producing hot air, the A/C was giving off cold air. I wound up driving car in the yard to a hill where I ran the car on an incline facing downhill…It began to overheat so i turned off car and when it cooled down I bled the radiator screw again…I then turned the car around to face uphill and sat there for 20+min. without overheating, I played with the Heat/AC, and the heat produced hot air and the AC produced cold air. I turned the car off and when it cooled down I bled the radiator screw again releasing trapped air until coolant came out…I felt comfortable with the car so I drove it back onto street and it ran in idle and me revving motor up every now and then while bouncing back and forth with heat and air for another 20+ min with no issues! it seemed the car facing uphill had got all the air out when it was bled, I was hopeful the car was fixed!

Until I went for a drive…the check engine light had been on since the water outlet pipe burst So I drove it to advance auto parts and it gave a signal of LOW COOLANT PERFORMANCE. this whole time I've been checking the coolant reservoir and so far it has been not leaking or lowering… I then left advance auto parts and drove around town…after about 15min of legit driving down highways the car which drove great began to overheat. I pulled over multiple times and the coolant was bubbling in the reservoir… I couldn't drive no more than 1/4 mile at a time until i got back home because it was overheating…at one time the coolant in the reservoir lowered down so i added some more…then the next pullover the coolant was bubbling out somewhere on the reservoir , i could see the wet coolant below the reservoir… i finally made it home …Im not sure where to go now

 

[BowtieGuy]

Unless I missed it, it looks like you still haven't tried the thermostat. Have you checked/replaced the thermostat yet?

 

[s0duva02]

Unless I missed it, it looks like you still haven't tried the thermostat. Have you checked/replaced the thermostat yet?

I ordered the thermostat, a new reservoir and reservoir cap...but still waiting to get it in the mail...I doubt the reservoir needed replacing but being only $30 for it with cap I figured it was worth it too to replace.

I am hoping the thermostat will fix the problem, with bleeding air out after installation...any more ideas would be appreciated

 

[carbon02]

While removing the thermostat inspect the wiring connection to it. I believe the thermostat itself is a traditional wax pellet. However, there's an electrical resistor near the wax pellet that is commanded on by the Powertrain module.

This inflates the coolant temperature in this area causing the thermostat to open.

Without the help of the resistor I had thought the thermostat opened somewhere around 230-240F, which is indeed pretty high temperatures, especially if you're fighting air pockets and boiling.

With a cold engine, cap off reservoir, I would think the small 1/2" line to the back of the water pump would pull some suction. Fluid flow would be through the tank, in heater core, out heater core, backside of water pump, through internal passages in the block, out water coolant outlet--back to heater core..

Some fluid also leaves the coolant outlet through the top connection which should be the highest point of the coolant system with the car on level ground. Air and coolant should be brought back to the tank, and with the tank cap open it should return.

With all the coolant hoses that you can't see that cool the Turbo, this coolant system is going to be a challenge.

When the coolant air bleed line, and the water outlet cracked no plastic parts got into the coolant system did they? Not sure how this could occur. If the thermostat failed and blew open, there could be plastic parts in the water pump passages. If the thermostat guts are missing, you may have to pull the pump for inspection.

I would start with the thermostat and then do the coolant bottle.

Thanks for your posts, and keep us updated, there's several of us following this thread

 

[s0duva02]

ok…so the parts came in. I cyphered out the coolant and replaced the reservoir and cap with no probs…looks good!
(I'm excited about how my coolant system looks…a major cruze nerd…only a cruze can get you thinking like that!)

I then pulled the thermostat and replaced it…attached is a pic of the thermostat being pulled off and the inside of the water pump. the thermostat was intact, it didn't look like it was broken in pieces…but i did notice that it had a rattle to it…this rattle you can hear without pulling off just by grabbing the coolant hose and squeezing. I thought maybe the rattle is proof its broken…but then i grabbed the new thermostat, which came with a new gasket, and it had a little rattle as well…so there goes that theory. THE THERMOSTAT IS SUPPOSED TO HAVE A SLIGHT RATTLE, Kinda sounds like a skittle rattling in there somewhere. With thermostat replaced I filled back up with coolant and cranked up car…

The check engine light was off! the car ran great. the heat was producing not 100% without revving motor but like 60-80% which was a lot better than old thermostat. but when car revved up it produced 100% heat. with engine light off, I assumed it was fixed..but still wasn't comfortable.

My personal opinion…the car does a decent job at getting air out its system on its own…when I had the car running i noticed the temperature gauge balance in-between 6-7 hash mark which is normal operating temp. ( using the very middle as hash #8.) but once or twice it bounced up to hash 8 but then it balanced right back out but more hugged hash 7. the fan ran on low for a minute and the reservoir bubbled a little but balanced back out. I drove car to walmart and grabbed some more coolant because it wasn't all the way topped off after i replaced the thermostat. I came home and car was running fine although a little hugging hash 7. it was late so i turned off car and went to sleep. next morning the reservoir was real low maybe 1/2" above lower hose connection so i topped it off with coolant.

cranked up car and drove to mcdonalds with heat on and everything was fine got in drive thru and the fan came on low but after a few minutes sitting it turned off and was fine idling… I got my coffee and drove down through town now with heat and air off. I thought maybe the heat being on helped the car get rid of heat so now lets drive with no heat on. I drove down through town with temp gauge still hugging hash 7. I got to a gas station after highway driving for a bit and idled…the temp gauge jumped up to the middle hash (8) and fan came on full blast! i kept it idling and watched it…it never went above 8 but obviously this isn't completely normal…so new thermostat is helping because it isn't completely overheating but still not 100% fixed. I revved the motor and the temp went back down to hugging 7 hash. I now am assuming the water pump isn't accurately pushing coolant as it should…Im thinking it is working just maybe not as efficient as it could (maybe due to it overheating in the past couple weekends)…It took the motor (revving it up) to turn the water pump harder to get the coolant to flow through to get the temp back down?? just a theory??
I then a little worried began to drive back home, i figured what the heck lets turn on the A/C and see how the car handles it…The fan went back down to low as i drove an interstate back home…it might have turned off but i can't discipher that at high speeds. When i got off the exit the fan was running on low and still the temp hugging hash7. I pulled over and checked the reservoir…still topped off and turned the A/C off…no difference…the check engine light came back on. I drove to advance auto parts and ran a diagnostic as i picked up my water pump…which is only $70 something dollars…the diagnostic said 3 times LOW ENGINE COOLANT FLOW…I drove back home now ready to swap out the water pump…as soon as the temp goes down i will cypher out the coolant and begin swapping out the water pump.

the water pump is not leaking…I don't think Im hearing any weird noises from it?? I still have my original water pump from years ago at 28-29k miles . i see it has a plastic piece that the propeller runs adjacent to…Maybe the overheating has warped that plastic keeping the propeller from spinning as free as it wants to…IDK?? when the water outlet pipe cracked it doesn't look like its missing a chunk of plastic? but maybe theres a piece wedged up against the water pump??? IDK??? I have flushed the radiator…which made no big difference…I have now replaced the thermostat…which did help …the car no longer crazy overheats but it does not regulate between 6-7 hash mark as it used to…it now hugs 7 and every now and then rises to 8. as the motor is revving above idle the coolant seems to be flowing enough to keep it from crazy overheating but idling is not enough to keep the coolant flowing enough to stay regulated.

thank you everyone for your advice and help…I am providing this much detail to maybe help the next cruzer…any more ideas are welcome...

 

[ChevyGuy]

What code is being set? Not the text, the number. I think I'd get an adapter and an app to monitor the various sensors. Then you can figure out what's going on.

Just guessing, you could have a failure of the thermostat control system, or excessive resistance in one of the senor circuits.

 

[jsusanka]

Step 6

trace gasket onto cardboard to make a template, this will help keep bolts organized and not mixed up, the water pump bolts can be pushed through the cardboard to remember its exact location...not all bolts are the same size...very important step, very easy to get confused on where the bolts return to. i did not have cardboard and just traced it onto paper.
View attachment 15505


by the way, the water pump was leaking from the weep hole located in picture below, not sure why picture has lines through it??

View attachment 15506


when the weep hole is blowing coolant, it means the seal is broke inside the water pump, its a warning sign the pump isnt working as it should.


step 7

proceed to remove the bolts off the water pump i believe there are about 10. remember to use the template to keep track of bolt placement.

when all bolts are removed pull of the water pump, this will take a little muscle, but not crazy muscle, make sure all 10 bolts are removed! there is a tab on left side of water pump about half way down that i used a wrench and pried off the pump from the block, again this did not take crazy amount of force!
View attachment 15508
sorry pics are green, my phone case is green and the flash reflects the color???

clean off the motor where old gasket residue is left, be careful not to gouge the metal.
View attachment 15509
this picture is before i cleaned it up.

Were you getting water on the ground by the oil drain plug and that is how you knew it was leaking? How did you see the weep hole before you started taking things apart?

 

[s0duva02]

Were you getting water on the ground by the oil drain plug and that is how you knew it was leaking? How did you see the weep hole before you started taking things apart?

This post pertains to my leaking water pump from 2012 when Ihad about 28-29K miles on the car. Icould tell I was losing coolant somewhere because the reservoir was emptyingfrequently and car would begin to overheat…I found the leak by inspecting thewater pump as the car was running…I noticed a 3-4 drop spray every 10-20seconds by looking from an angle with flashlight under the water pump pulley…themotor was running so I had to be careful but I did finally see that leak…I thinkit might have only been noticeable while under pressure and pump rotating… I don’tremember 100% because it was a few years ago.

 

[s0duva02]

IT IS FIXED AGAIN....AT LEAST FOR ANOTHER 50,000 MILES!


With my suspicion that the plastic in the water pump is warped I got the new water pump and printed off page 1/2 of this forum feed for the directions to make sure I didn’t forget a step. Every step came back to me as I was removing the old water pump. And just as I suspected…theplastic around the old water pump propeller had warped and busted into pieces…the propeller itself would still spin but the broken plastic was hindering the flow of coolant.



I removed the broken plastic pieces as much as I could, and flushed from the other side of the motor…nothing but coolant came out but I am not 100% sure every piece is removed from inside the motor…nothing else I could really do except install the new water pump and try it out.



After installing the new water pump and connecting everything back together I filled with coolant and the car did a great job of removing airbubbles from the coolant lines on its own…



So far I have driven the car around town for a day and now to work this morning, check engine light disappeared, never overheated again…I am confident that the car is back in normal operating condition between 6-7 hash mark but closer to hash 7. Normal as long as I don't have any surprises from plastic pieces that may or may not still be in the motor.

The radiator fan has come on low from time totime of long idling, but that is normal…it has come on and hit the low and mid-levelfan speed for when the A/C is running and long idling, but again normal… I am a big believer in the cruze that if the radiator fan goes to TOP NOTCH HIGH JETSPEED, pretty much takes over the sound of the motor and everthing around you, then you need to at least be concerned that maybe something isn’t working aswell as it should…but IDK im not a professional mechanic...thank yall for your help

my theory was that my thermostat failed, which caused the car to overheat which warped and broke the internal plastic and the heat also cracked the plastic water outlet pipe...COMPOUND PROBLEMS are always the hardest to troubleshoot.

 

[ChevyGuy]

my theory was that my thermostat failed, which caused the car to overheat which warped and broke the internal plastic and the heat also cracked the plastic water outlet pipe...COMPOUND PROBLEMS are always the hardest to troubleshoot.

It might not be a bad idea if you're changing one of them, to change all three while you have the coolant out anyway. Especially if an overheat is involved.

 

[NickD]

Ha, changing the water pump sounds much better to something that is reliable. Rather than replacing it with one of equal crap value.

In scanning over the posts, not really talking about changing the water pump, just replacing it. Is a difference.

 

[carbon02]

IT IS FIXED AGAIN....AT LEAST FOR ANOTHER 50,000 MILES!


With my suspicion that the plastic in the water pump is warped I got the new water pump and printed off page 1/2 of this forum feed for the directions to make sure I didn’t forget a step. Every step came back to me as I was removing the old water pump. And just as I suspected…theplastic around the old water pump propeller had warped and busted into pieces…the propeller itself would still spin but the broken plastic was hindering the flow of coolant.



I removed the broken plastic pieces as much as I could, and flushed from the other side of the motor…nothing but coolant came out but I am not 100% sure every piece is removed from inside the motor…nothing else I could really do except install the new water pump and try it out.



After installing the new water pump and connecting everything back together I filled with coolant and the car did a great job of removing airbubbles from the coolant lines on its own…



So far I have driven the car around town for a day and now to work this morning, check engine light disappeared, never overheated again…I am confident that the car is back in normal operating condition between 6-7 hash mark but closer to hash 7. Normal as long as I don't have any surprises from plastic pieces that may or may not still be in the motor.

The radiator fan has come on low from time totime of long idling, but that is normal…it has come on and hit the low and mid-levelfan speed for when the A/C is running and long idling, but again normal… I am a big believer in the cruze that if the radiator fan goes to TOP NOTCH HIGH JETSPEED, pretty much takes over the sound of the motor and everthing around you, then you need to at least be concerned that maybe something isn’t working aswell as it should…but IDK im not a professional mechanic...thank yall for your help

my theory was that my thermostat failed, which caused the car to overheat which warped and broke the internal plastic and the heat also cracked the plastic water outlet pipe...COMPOUND PROBLEMS are always the hardest to troubleshoot.

I'm glad you got this resolved. I know you're one of the few people running an aftermarket water pump, due to your car not having the extended warranty on the water pump. Was the original pump that you removed a plastic impeller, or was that one metal? Are both plastic, in which case it doesn't make much of a difference which one someone may use, or is the factory one a metal unit?

This may be something to watch as these cars get older, and more people are doing water pumps themselves.

 

[s0duva02]

I'm glad you got this resolved. I know you're one of the few people running an aftermarket water pump, due to your car not having the extended warranty on the water pump. Was the original pump that you removed a plastic impeller, or was that one metal? Are both plastic, in which case it doesn't make much of a difference which one someone may use, or is the factory one a metal unit?

This may be something to watch as these cars get older, and more people are doing water pumps themselves.

The original water pump came with a plastic guard as well but it did not crack. interesting note, the original water pump had a metal gasket while the aftermarket ones are a felt/paper type of gasket.