Coolant loss!

[~tc~]

So, continually getting air in the system- or the coolant level in the reservoir always requires top ups- indicates a problem.....

No, on a new car, it doesn't necessarily, per your own "analysis":

In a Kizashi, any air in the engine cooling system will bleed out through the reservoir- with the natural expansion/ contraction cycle of the coolant. The coolant expanding will force any air, past the pressurised radiator cap, into the reservoir. When the engine cools, the reservoir is designed to only allow coolant to return to the engine (providing the level is kept between the high and low markers.)

Without any evidence the coolant is leaking out or being burned in the head (white, sweet smelling smoke from tailpipe), the logical diagnosis is the system needs to be bled.

[KuroNekko]

Keep in mind that all modern vehicles have a "drip tray" built into the plastic cover under the engine. It's designed to stop oil leaks from dripping onto the road, but could also catch a significant amount of coolant before it dripped out underneath the vehicle. There's usually an absorbent pad on the tray to catch fluids.

So, if there did happen to be a slow leak, it's quite feasible that there would be no drips. The coolant could also be evaporating from the tray in between drives.

These are actually for aerodynamics and noise reduction. They serve as drip catchers, but the intended purpose is for improving aerodynamics under the car for improved fuel efficiency.

How's that even remotely relevant to coolant being lost?

Those are not drip trays. That's not their function.

[SamirD]

+1 on the bad radiator cap. Make sure you put it on snug and close it all the way. If it keeps leaking, replace it. A bad/loose cap will cause the cooling system to depressurize. When it depressurizes, the boiling temperature of the coolant lowers so it boils easier. Boiling will cause the coolant to leak out and/or evaporate.

I've seen this before in my Accord. So the question you need to ask yourself, is how did that coolant get there and then dry up? Look for the obvious first--cap, hoses nearby, etc. And then move to other possibilities like the overflow tank.

What's the temperature like in Tehran? That will make a difference too.

[SamirD]

If you don't want to make a trip to the dealership, and don't mind investing in a tool, get a coolant system pressure tester:


I have this exact same tester and it's under $100 and a worthwhile investment since it works on any car with the right cap adapter.

You can use this to diagnose your entire cooling system in one shot. I've diagnosed cut hoses (that I thought was a water pump from the puddling), as well as a cracked radiator (which wouldn't leak until it was under high load).

You take this tool and attach it where your cap would normally be. Then you pump the tool to apply pressure to your cooling system, but not too much! You shouldn't exceed the factory specs. Once you are at factory specs or close to it, you should see exactly where your leak is spraying from.

[murcod]

Yes, they're an excellent tool as you can pressurise the coolant system with a cold engine. No burnt hands!

[~tc~]

You can rent/borrow them from most auto parts stores (in the US anyway)

[amoows]

murcod, ~tc~ and KuroNekko have helped a lot with their explanations. Thanks.

What's the temperature like in Tehran? That will make a difference too.

Let’s say over the course of a year, the temperature in Tehran typically varies from 1°C to 36°C and is rarely below -5°C or above 40°C. Currently is -3m though with light snow.

So the question you need to ask yourself, is how did that coolant get there and then dry up? Look for the obvious first--cap, hoses nearby, etc. And then move to other possibilities like the overflow tank.

I did mention in my recent post that I most likely know how the coolant is disappearing! Through the very small overflow hole on top of the reservoir, as seen in the pictures. See: http://kizashiclub.com/forum/viewtopic. ... 429#p24429

You should be checking the reservoir level only after the vehicle engine has completely cooled - this will take a long time.

After each drive, check the coolant in the overflow tank right after you park. Also, when adding coolant, add it directly to the radiator if it's low, not the overflow tank.

I keep checking the level of coolant on the reservoir tank, whether the engine is cooled, or is warming up, or even when it has been running for some time. When the engine is cold, the level is lower comparing to when it has been running for a while, as logically expected. HOWEVER, after each drive, when the engine is cooled down (let’s say the next morning), the level is lower than previous day/time!

So, continually getting air in the system- or the coolant level in the reservoir always requires top ups- indicates a problem...

The car is brand new and as ~tc~ mentioned, the logical diagnosis could be (hopefully) the system needs to be bled. But I am getting worried that something serious may cause this problem. As far as I can tell the radiator cap is fine and I have found where and how the coolant is leaking/bleeding but I am still trying to figure out WHY!
Today, I have cleaned the area off blue stains, with a commercial steam cleaner, and I am going to observe and study more carefully for another two/three days.

[~tc~]

If it really is air, you should be putting in less and less each day, I would have expected you to purge all the air by now!

Oh, and by the way, your English is excellent for a country so politically isolated as Iran!

[murcod]

Top it up in the morning (when it's totally cooled down) and get it to the "HIGH" mark. Don't bother looking at the level again until the following morning when the engine has cooled down again. See how the levels compare - it should be the same.

Coolant shouldn't ever flow out the overflow hole - unless the reservoir has been over filled. (Or the engine has other issues- which your Kizashi certainly shouldn't.)

As mentioned previously- you shouldn't need to be touching this on a new car. Even topping up once would be highly unusual.

[SamirD]

Oh, and by the way, your English is excellent for a country so politically isolated as Iran!

You'd be surprised at how fluent the rest of the world is in English--many times better than we Americans.