coolant res ?

quick question for you guys and girls. I opened my hood to look at a headlight that I had out and I noticed that the black coolant cap was not seated properly. I looked down in it and there is a little bit of crystalized pink coolant around the lip. there is barely any coolant in the bottom of the reservoir. its below the low line. don't know if that's normal or just an overflow? don't know much under the hood sorry don't laugh. truck has been running fine. haven't smelled or seen anything. any help would be appreciated.
by the way...2015 Tacoma 28k miles

 

I may be mistaken but isnt that the winshield washer fluid resevoir?

 

No.... it's close to the wiper fluid. Def connected to the radiator. Fluid is pink.

 

If there is a small rubber hose running to the radiator then its the overflow tank for the radiator. Which when the motor is hot the fluid expands and overflows into the reservoir. When the coolant cools down again and contracts it'll create vacuum and suck the fluid right back into the radiator.

There should be two "lines" on the overflow tank for cool and hot. When the motor is cool is should be at that line.

If its the widow fluid washer reservoir it'll have a pic on the lid.

 

At the dealer now. Said it is overflow and some should be there but not full. Going to check it out and fill. Will mark it and log it because I want it noted before 36k

 

When the motor was cold I looked in the radiator and it was full. Service guy thinks maybe because the reservoir lid wasn't sealed all the way maybe it evaporated.

 

Yeah as long as the radiator is full. The fluid in the overflow is "extra".

 

I guess my ? Is if it is just an overflow and I kinda understand now how it works, it "should" have something in it correct?

 

Yeah for sure. There are usually markings on the side. There are on my 17 at least.

 

There is. That's the only reason why I posted this. I would only assume if my tank says low & full then it suppose to have fluid in there. I think in the bottom I have a couple tablespoons worth in there. I suppose it's possible that it evaporated because the lid wasn't properly sealed. Idk

 

Right on. I usually check fluids like that when I check my oil. I'll have to keep an eye on the reservoir lid. Thanks

 

Absolutely.