[Big200c]

I have a 2016 200c with 133k on it. I bought the car 10k mi ago and when I first got it I noticed the coolant reservoir cap was not on right and it had leaked a little out. I refilled the reservoir with right under 1/2 gallon of factory spec "OAT" coolant.
Shortly after I flushed the coolant system several times and refilled the system with a "Universal All Mix" coolant and replaced the reservoir cap with a new one..

Now I'm noticing I'm having a loss of liquid coolant of about 1/4" in the reservoir every 1000 miles. I can't visually find any leaks anywhere, and I'm not getting any excess dripping out of the exhaust or any coolant smells from the exhaust..
Are these cars known for having any issues with the coolant reservoirs cracking or any coolant leak issues???
Any ideas what's going on here??

Note; The "Universal All Mix" I filled the system with is almost odorless, so smelling a leak is hard to notice. Can't visually see a leak anywhere.

 

[200_S_AWD]

A slow leak might evaporate first before reaching the ground. I had this happen on the Caliber. I would step in front of the car after a drive & catch a whiff of hot coolant once in a while. The reservoir did drop very slightly over a couple of months.
If the reservoir has a pressure cap, there shouldn't be any evaporation. On cars with a jug & filler cap, there may be some evaporation of the 50/50 water-component of the coolant.
I finally found the leak by looking up under the car and seeing the dried trail of coolant drips. It was the upper hose, a leak that I didn't see from above.

Does the 'Universal All Mix' say that it meets Chrysler MS-12106 on the label? Distilled or very soft water is recommended. A proper 50/50 concentration is important.
Avoid using 'Stop Leaks' they are a bandaid & can clog small heater core passages.
The common leak points are at joints & juncitions. Some fittings & pipes that should be aluminum, are made of plastic.
A pressure tester (loan from a parts store?) may 'speed up' a leak & make it easier to find.

 

[Big200c]

A slow leak might evaporate first before reaching the ground. I had this happen on the Caliber. I would step in front of the car after a drive & catch a whiff of hot coolant once in a while. The reservoir did drop very slightly over a couple of months.
If the reservoir has a pressure cap, there shouldn't be any evaporation. On cars with a jug & filler cap, there may be some evaporation of the 50/50 water-component of the coolant.
I finally found the leak by looking up under the car and seeing the dried trail of coolant drips. It was the upper hose, a leak that I didn't see from above.

Does the 'Universal All Mix' say that it meets Chrysler MS-12106 on the label? Distilled or very soft water is recommended. A proper 50/50 concentration is important.
Avoid using 'Stop Leaks' they are a bandaid & can clog small heater core passages.
The common leak points are at joints & juncitions. Some fittings & pipes that should be aluminum, are made of plastic.
A pressure tester (loan from a parts store?) may 'speed up' a leak & make it easier to find.

View attachment 62334

The water that I flushed out the original OAT coolant with was distilled water, and the coolant is a 50/50 pre-diluted All Mix that is recommended for all makes and all models regardless of year and manufacturer. After flushing I did use one full gallon of regular straight non diluted All Mix coolant because of the amount of distilled water that was still left in the block that would not drain out completely, and then topped it off with another almost full gallon of the pre-diluted 50/50 All Mix coolant.

I was considering getting a pressure tester but this system is considered a sealed pressurized cooling system, and after the car has sat for days I slowly open the cap on the reservoir and it does release pressure and gurgles, so even after sitting for days the system is still holding some pressure, How much pressure I'm not sure, but it's definitely not an extremely high pressure as when the system is warmed up and running.
I appreciate Your suggestion and Pic of looking at it from underneath I'm definitely going to take a good look at it now, you have me thinking it's a very small very slow leak coming from somewhere from somewhere around that area..
Oh and thanks for the info video too!

I appreciate it, Charlie

 

[Rylin87]

I remember at the dealership when these Fiat influenced cars came out it seemed like all of them had coolant crust around all the hose ends and quick connect fittings, and these were cars with very low mileage. Also I would not have used universal coolant. Unless the vehicle is a total POS I never use ‘all makes all models’ fluids. Who knows how the different coolant will react with the seals and metals. Also coolant can turn into jello when different types are mixed and basically ruin the car. As long as you got 100% of the old coolant out you should be ok with that.