[RickOntario]

Hi, I traced a coolant leak on my 2012 CR-V (EX-L AWD) to the coolant temp sensor located on the lower left side of the radiator. I have pulled apart all the hoses and the front bumper to remove the radiator and take a better look. The plastic housing around the sensor looks fine and so does the sensor. The O-ring looks fine too (visually). All I could see was that the sensor seems to have been over-tightened by some technician at some point because a little bit of the plastic around the sensor bolt was chipped in.
I did a vacuum leak test of just the radiator (see picture below) and the system lost pressure within 30-60 seconds.. I can only guess that it's leaking out of the coolant temp sensor bolt.
Could any of you advise on what should be my next course of action - should I just replace the O-ring or should I get a new sensor or should I replace the entire radiator?
Thanks to everyone in advance. -Rick.

 

[Avisitor]

Vacuum test of radiator?
Wouldn't the radiator cap allow for fluid or air to flow back into the radiator as it cooled in normal operation?
As far as I know, radiators are pressure tested??

Would fill with water and pressurize the radiator to see where it is leaking.

 

[RickOntario]

Vacuum test of radiator?
Wouldn't the radiator cap allow for fluid or air to flow back into the radiator as it cooled in normal operation?
As far as I know, radiators are pressure tested??

Would fill with water and pressurize the radiator to see where it is leaking.

I used the 'cooling system test and refill kit' (from Harbor Freight), it has adapters to seal the radiator cap and creates a vacuum to check if there are any leaks, if the vacuum holds then you know there are no leaks. The same device then allows you to refill the system with coolant without the need for burping the coolant lines.
Link to the tool I used: Cooling System Test and Refill Kit

 

[Avisitor]

Not a fan of Harbor Freight tools for testing vehicles.
But, if you are confident in it then so be it.
However, a vacuum will not let you see where the leak is
A pressurized test would should where the leak is??
No guessing??

 

[RickOntario]

Not a fan of Harbor Freight tools for testing vehicles.
But, if you are confident in it then so be it.
However, a vacuum will not let you see where the leak is
A pressurized test would should where the leak is??
No guessing??

You are right! After your comment I did some researching on the web, I think I'm using the wrong tool to detect my issue. I'll purchase a pressure tester pump kit and fill with water and try to find the leak. For good measure I'll get a new O-ring for the coolant temp sensor to see if that makes a difference.
My CR-V was sitting out in a parking lot for the past 3 months in Buffalo (also during the recent snow storm).. all the brake pads/rotors are shot and calipers look like they've come out the bottom of the ocean.. I have a feeling the corrosion did something to the radiator and this sensor housing..
Thanks a lot Avisitor for your feedback, helped a lot! Cheers 🍻

 

[Avisitor]

If the brake rotors are rusted the try running the vehicle with short tests on brakes
Sometimes it will clean itself off. Why not test before replacing?
If it clears up then run with it until you can actually inspect it??
If it does not clear up then you know for certain to do the brake job??

I wish you lots of luck and hope it is something simple and cheap to fix

 

[RickOntario]

If the brake rotors are rusted the try running the vehicle with short tests on brakes
Sometimes it will clean itself off. Why not test before replacing?
If it clears up then run with it until you can actually inspect it??
If it does not clear up then you know for certain to do the brake job??

I wish you lots of luck and hope it is something simple and cheap to fix

Yes, I did some short drives, the rotors are warped and the rear calipers have seized. A brake job was never performed on the car as it was driven very less (has only 55k miles). So I've decided to go ahead and complete the job while I overhaul the rest of the components. The A/C condenser has lost a third of its fins, so I'm considering replacing that as well.. I have heard A/C compressors go bad on this gen of CR-V's and send metal fragments all through the cooling lines, have you heard/seen anything similar?

 

[Carbuff2]

have heard A/C compressors go bad on this gen of CR-V's and send metal fragments all through the cooling lines,

You seem to be thinking of the Gen2. Your car might be subject to a worn compressor clutch.

For the radiator: Can't you borrow a pressure tester from an auto parts store? You can in the USA.

 

[patruns]

I see corrosion on the outside of the brass fitting, not the inside where the o-ring sits. I would be looking outside. That plastic connection seems suspicious to me.

 

[RickOntario]

You seem to be thinking of the Gen2. Your car might be subject to a worn compressor clutch.

For the radiator: Can't you borrow a pressure tester from an auto parts store? You can in the USA.

oh ok.. I'll research on the compressor clutch then..
I'll have to find out from a local parts store if they have any for rent

I see corrosion on the outside of the brass fitting, not the inside where the o-ring sits. I would be looking outside. That plastic connection seems suspicious to me.

Ya.. the plastic was a little 'bitten into' by the sensor bolt.. not sure if the previous tech over-tightened it and if so, why it started to leak now of all times.. I'll check that area with pressure tester..