Honda city dropping water level in the coolant reservoir

[i.m.hammid]

Hi Respected PakWheelers,

This is going to be a little long as I will post my each and every observation. Please read through and help.

So I bought this Honda City 09 model last month. I got the car inspected before buying and everything was good and car ran perfectly.

When I was driving home after the purchase, I noticed the heater wasn't working. (My bad I did not check it before hand.) So I called the previous owner on my way back home and asked about it. He said he doesn't know or maybe the heater/AC knob wasn't working and I should get it checked.

So after a week or so, I took the car to AMX Honda Center in I-10 islamabad to get it completely serviced. I asked them to check the heater too. They checked and told me that the heater hose is disconnected. So I asked them to fix it and they just reconnected and ran the heater, it was working fine. I was satisfied and I drove home with the heater on afterwards.

I'd like to mention here that this is my first car, I could not possibly have known that heater could've been disconnected because of a leakage in heater radiator. And AMX Honda should have known this, but THEY STILL JUST CONNECTED THE HEATER WITHOUT CHECKING FOR LEAKS!!!

So I came home and parked my car. In the night I went for some late night cruising and to get some snacks. I was hardly 01 KM from home and there was a red light in my cluster, I noticed it and stopped the car. Then I waited for the car to cool down, and drove back to home @ 10 speed.

Then I started researching.. I was really worried and knew whatever happened, it happened at today's service. I checked my Radiator was just dry and empty.

Next day, I brought in a local mechanic and I asked him to disconnect the heater again.. After that, I topped the radiator with water and drove. All Good !!!

By this time, I had done enough research to know that I might've blown my engine.

So tomorrow I did the following:
1) I checked for any water pressures in the radiator while starting the engine - Result: It was fine. Nothing abnormal here
2) I also checked my engine oil cover to see if there's any milk shake stuff. Result: That is fine too!
3) I checked for any extra smoke: All seems fine here too.

I thanked God and topped the radiator and closed the cap.

And then I started driving but keeping a very close watch on water levels in my coolant reservoir.

Here are my findings:
Water level in the coolant reservoir drops very little. After every trip the coolant level drops a little. But it does not drop significantly. I drove 250KMs in a day, and the water level in coolant reservoir only dropped like an inch.
Sometimes it drops an inch by just a 30-35KM trip.

I've been noticing this behavior for almost 02 weeks now and I never opened the radiator cap during this time.
Car never heated. Again!

So kindly tell me what could be the reason behind this little water level drop in the coolant tank?

I really appreciate your help in this regard.

[xhaikh1]

As your car is perfectly fine as you described in your above story you just have to open the rafiator cap while engine start fill the coolant till the radiator fan does not turned on, because there is the thermostat valve which blocks the circulation of water till the engine temperature reaches to it level then the circulation starts so when you poured the coolant it that valve was closed because of cold engine.

Now you just have to open the radiator cap while cold engine fill up then start the engine and fill it again radiator till your radiator fan does not turn on.

After doing this all, still the water decreases then you have to clean your radiator,it will choked from inside.

[xhaikh1]

This process is called bleeding of coolant in rafiator when the air is locked in cooling system. Its normal behaviour whenever the radiator coolant gets completely empty, then is air in the which has to be escaped by bleeding as described in the above process. If you still dont understand the process you also can google that how to bleed the coolant system

[i.m.hammid]

@xhaikh1 thanks for taking the time and answering my question. I really appreciate it.

I understood your point. I just have a counter question.

Whenever the water level dropped to MIN, I topped it to MAX level in the tank. This happened 02 times in past two weeks. Since that water is being sucked into the radiator, does that indirectly bleed out the cooling system over time? Or do I have to directly bleed the system by opening radiator cap and toping water until the fans turn on?

[flyingfeather]

@i.m.hammid f it's a little drop, as you have mentioned it is normal. I am the first owner of 2016 model city, it used to reduce coolant especially after a long journey. Asked a couple of mech trusted ones, all said it's normal. Stop using water, get the cooling sys serviced and pour in some good coolant. Don't visit honda 3s, those morons are good at replacing things only. They have no clue of repair, diagnose or service.
They connected the heater core without washing/servicing it, which is a big blunder. All that muck and dust going into cooling sys could have chocked the radiator. Now get the radiator cleaned, if you are willing to spend on heater core do it and use coolant thereafter. Good luck

[i.m.hammid]

Thanks @flyingfeather for your response. I really appreciate it.

After that first experience, I am never going to Honda 3S again. Those guys are just stupid.

I am planning to get my heater core replaced/fixed, and then flush out my cooling system and add the Caltax concentrated coolant with distilled water. But before that, I just wanted to diagnose why am I losing the coolant in the expansion tank.

For reference, a friend of mine also has a city 2012, and he never ever lost coolant. So this is making me worry that there might be an issue with my car, especially after that overheat sign in my cluster. These stupid cars don't have a heat guage. they just blink up when the car has reached its heating threshold.

I really hope this is normal as you've mentioned it.

[xhaikh1]

Filling out the reservoir bottle will take time so you have to bleed it out directly

[tg1]

Is there rust inside your radiator?

[i.m.hammid]

No, last time I opened the radiator, there was no sign of rust whatsoever.

[roony]

For reference, a friend of mine also has a city 2012, and he never ever lost coolant.

It is normal to lose a little over time, especially if your driving for a while. The coolant reservoir isnt 100% pressurized, it just has a plastic cap so some coolant could evaporate through it. I have seen this on brand new citys.

If your having to refill from min to max in 2 weeks thats not normal. But you are using water and also maybe you still have air in the system. Get the heater core fixed, check for leaks then replace with coolant, bleed the system. Below can help you see the replacement procedure.

Water Pump Inspection - Coolant.pdf (732.0 KB)

[flyingfeather]

First thing first. Get the radiator cleaned heater core fixed and coolant poured. In case of even a minor leak, coolant will leave a dye mark, making it easier for you to find the leak. I am still of the opinion that this much drop is normal. In summer season with ac on the drop will be even more.

[i.m.hammid]

Thank you @roony and @flyingfeather for providing your valuable opinion.

So in the past week, I finally got some time so I got the heater core replaced. Got a Kabli heater core from Sultan ka khoo in Rawalpindi. Here is a picture of my leak heater core:

I did not replace water with coolant right after heater core replacement as I wanted to be sure there's no leakage from the new core before I invest in the coolant.

So far I have driven about 100KMs after the heater core replacement. There is no leakage (Thank God). But I am still seeing that small water level drop in the expansion tank.

I am planning to replace the water with coolant on this weekend if I could spare some time. Will post the update here.

[flyingfeather]

Great . a little drop is fine. Keep coolant bottle to top up the reservoir. Subsequently if you find time get the sys diagnosed by some competent mechanic

[i.m.hammid]

Ok guys, so yesterday I went to swap the water with coolant.

But before that, I asked the mechanic to check for any possible leaks. I told him that my water level in expansion tank drops from MAX to MIN every 700-800KMs. He was saying this is normal, but I still insisted on checking for any possible leaks.

He did an examination of the cooling system, and said there's no leakage. But there might be a very tiny seepage though a hose pipe, as there were some white minerals stuck on the pipe joint. He said the seepage is very minimal so water evaporates as soon as it leaks so the white minerals like stuff is accumulated at a joint.

Here is the picture I took:

So he said either to replace the hose pipe, or he could remove the pipe, apply some silicon and then replug it again. I asked him to apply the silicone. (I did not replace the pipe right away as the seepage was very minimal and could not be diagnosed for sure, this was just a speculation or intelligent guess of the mechanic. I thought if this is indeed the problem, then either applying silicone will fix it, or I will see the coolant color here instead of white minerals stuff and then I will know for sure this is the culprit and then I will get the hose pipe replaced)

Well, after that, I also swapped water with genuine Honda Type-2 coolant in my radiator.

Fingers crossed, will post updates here.

[i.m.hammid]

Alright guys, since my last update I've driven almost 2K KMs and I've been monitoring the coolant levels in my car. The coolant level has not dropped even a drop. Finally I can safely say that there's nothing wrong with my car.

Lesson learned: Mechanics, even the Honda center ones tend to make mistake, since they have no stakes even if something goes bad because of their idiocy. Try to learn about the issues your car is having, read forums/Pakwheels and then you will definitely save yourself a lot of trouble.

Thanks guys for all your help. Much appreciated.