Coolant leak the reservoir is full?

2013 CHEVROLET CRUZE
123,000 MILES • 1.4L • 4 CYL • TURBO • 2WD • AUTOMATIC
Avatar
BHAMDOC1
  • MEMBER
  • 100 POSTS
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
Jan 17, 2026 at 12:20 PM
Advertisement
Avatar
BHAMDOC1
  • MEMBER
  • 100 POSTS
MAYBE BLEEDING?
Jan 17, 2026 at 1:04 PM
Avatar
BHAMDOC1
  • MEMBER
  • 100 POSTS
I bled it from the screw on radiator same thinf reservoir boiling, i have heat in the cabin, gauge not overheating, strange
Jan 17, 2026 at 2:27 PM
Advertisement
Avatar
STRAILER
  • CERTIFIED EXPERT
  • 53,854 POSTS
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.

Jan 19, 2026 at 7:03 AM
Avatar
BHAMDOC1
  • MEMBER
  • 100 POSTS
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?
Jan 19, 2026 at 7:07 AM
Avatar
STRAILER
  • CERTIFIED EXPERT
  • 53,854 POSTS
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.
Jan 19, 2026 at 7:15 AM
Avatar
BHAMDOC1
  • MEMBER
  • 100 POSTS
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
Jan 19, 2026 at 7:27 AM
Avatar
STRAILER
  • CERTIFIED EXPERT
  • 53,854 POSTS
Yep, it has got to be something from the work that was just done. Please upload a video of the leak if you can.
Jan 20, 2026 at 9:11 AM
Avatar
BHAMDOC1
  • MEMBER
  • 100 POSTS
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
Image (Click to enlarge)
Attached Media
Jan 20, 2026 at 5:21 PM
Avatar
STRAILER
  • CERTIFIED EXPERT
  • 53,854 POSTS
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?
Jan 21, 2026 at 9:00 AM
Avatar
BHAMDOC1
  • MEMBER
  • 100 POSTS
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
Jan 21, 2026 at 9:02 AM
Avatar
BHAMDOC1
  • MEMBER
  • 100 POSTS
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?
Jan 21, 2026 at 9:09 AM
Avatar
STRAILER
  • CERTIFIED EXPERT
  • 53,854 POSTS
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?
Jan 21, 2026 at 9:26 AM
Avatar
BHAMDOC1
  • MEMBER
  • 100 POSTS
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
Jan 23, 2026 at 5:47 PM
Avatar
STRAILER
  • CERTIFIED EXPERT
  • 53,854 POSTS
Sorry, I am not sure what you are saying here and you give more details, images?
Jan 24, 2026 at 10:54 AM
Avatar
BHAMDOC1
  • MEMBER
  • 100 POSTS
The coolant reservoir has a crack
Jan 24, 2026 at 10:57 AM
Avatar
STRAILER
  • CERTIFIED EXPERT
  • 53,854 POSTS
That is easier than the timing cover at least. Good find. Thanks for letting us know, Ken
Jan 25, 2026 at 8:24 AM