Coolant leak the reservoir is full?

Tiny
BHAMDOC1
  • MEMBER
  • 2013 CHEVROLET CRUZE
  • 1.4L
  • 4 CYL
  • TURBO
  • 2WD
  • AUTOMATIC
  • 123,000 MILES
After finishibg the timing chain job including a new water pump car runs great then fan comes on even though its not running hot, no codes. I see water dripping from around the crank shaft pulley, checked the water pump hose that goes to water heater its fine checked around water pump am not seeing anything leaking. Checked thermostat not leaking. Also the reaervoir is full and boiling and the hose around it which has no clamps starting to leak some mist from the pressure. The low radiator hose going to thermostat is not full or that hot. Am not sure what is going on. Car was not running hor before the chain job
Saturday, January 17th, 2026 AT 12:20 PM

16 Replies

Tiny
BHAMDOC1
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MAYBE BLEEDING?
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Saturday, January 17th, 2026 AT 1:04 PM
Tiny
BHAMDOC1
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I bled it from the screw on radiator same thinf reservoir boiling, I have heat in the cabin, gauge not overheating, strange
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Saturday, January 17th, 2026 AT 2:27 PM
Tiny
KEN L
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Hmm, can you lift the car and with a flashlight see where the leak is coming from? Please go over this video and guide to help.

https://www.youtube.com/watch?v=W8kra65m15c

and

https://www.2carpros.com/articles/car-is-leaking-coolant

Please upload a short video in your response of the problem, so I can see what's going on.

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Monday, January 19th, 2026 AT 7:03 AM
Tiny
BHAMDOC1
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Ya I have to see where it is coming from, could be from the dang water pump which is new. Do you usually put silicone on top of the gasket that comes with it? I did put a little. If there is a leak then the system is not pressurized and air goes into the system and can cause it to show up in the reservoir and boils, am I not correct?
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Monday, January 19th, 2026 AT 7:07 AM
Tiny
KEN L
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If the water pump is leaking it can pull in air into the system but that is rare. I would do a head gasket chemical check. Please go over this video.

https://www.youtube.com/watch?v=5zpNjYmmiYY

Please go over this guide and get back to us.
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Monday, January 19th, 2026 AT 7:15 AM
Tiny
BHAMDOC1
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No signa of a head gasket from wven before this job, no codes or misfires. I drove this car for days before this job, so I doubt. Engine is smooth. And no mixing at all. No water leaks or level decrease before this job, so hard to imagine. Ill check the leak and see
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Monday, January 19th, 2026 AT 7:27 AM
Tiny
KEN L
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Yep, it has got to be something from the work that was just done. Please upload a video of the leak if you can.
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Tuesday, January 20th, 2026 AT 9:11 AM
Tiny
BHAMDOC1
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I removed the mount and the bracket again, turned out coming from a 12 mm bolt that comes already tightened on the new cover. Supposed to be a torx one but since its after market they used a 12 mm, only had to tighten it a bit and it stopped seeping. Its the bolt on top of where am pointing
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Tuesday, January 20th, 2026 AT 5:21 PM
Tiny
KEN L
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But, there is no coolant in that part of the cover, are you sure it was not coming from the water pump? Does the timing cover have a crack in it?
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Wednesday, January 21st, 2026 AT 9:00 AM
Tiny
BHAMDOC1
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No cracks, it's a new cover, there is a bolt in the original and the new cover that is below the water pump, not sure what it's for. It was just not tight enough, it sits right below the pump, ya am 100% sure it was from there and no more leak is coming from it
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Wednesday, January 21st, 2026 AT 9:02 AM
Tiny
BHAMDOC1
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What is that screw for then in the original cover if you know plz, maybe to see if a water pump is bad? Like a weeping hole?
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Wednesday, January 21st, 2026 AT 9:09 AM
Tiny
KEN L
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I don't know what the bolt is for, All I know is coolant is not there on the cover. If you remove the bolt is the hole sealed, can you look with a flashlight?
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Wednesday, January 21st, 2026 AT 9:26 AM
Tiny
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When the reservoir started to boil initially I removed the thermostat to see if that is the issue. But theb the car would stay cold and would not even get to 1/4 the temp needed so installed a new one. Then waited to see and found the smaller hose that goes to the reservoir is steaming, so I wifgled it a bit and it was obvious there is a crank in the reservoir so I ordered one
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Friday, January 23rd, 2026 AT 5:47 PM
Tiny
KEN L
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Sorry, I am not sure what you are saying here and you give more details, images?
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Saturday, January 24th, 2026 AT 10:54 AM
Tiny
BHAMDOC1
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The coolant reservoir has a crack
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Saturday, January 24th, 2026 AT 10:57 AM
Tiny
KEN L
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That is easier than the timing cover at least. Good find. Thanks for letting us know, Ken
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Sunday, January 25th, 2026 AT 8:24 AM

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