[GForceEnjoyer]

Our 2006 Ford Fiesta 1.6 petrol recently overheated in traffic due to a stroke of terrible luck: a coolant leak as well as a cooling fan failure. Thankfully, we were able to pull over quickly, avoiding any damage.

Now here's why this thread exists: once we got the car back from the authorised dealer, I was horrified to see that the coolant level in the reservoir was far above maximum! A serious lapse in workmanship as well as quality control. The service experience this time (and the last few times too) was also underwhelming at best, which is why my dad and I decided to take matters into our own hands, removing the excess coolant at home.

Required parts:

1. Soap dispenser pump (a long pipe is necessary)
2. Sufficiently wide-mouthed container that can be held with one hand
3. Gloves/cloth for handling the coolant reservoir cap
4. A light source (if in a dark basement)

Time taken: 5 minutes, although this can vary a bit depending on the pump used and on the quantity of coolant to be removed.

Here's the soap dispenser pump we used. It must be absolutely clean, since it will be coming into contact with coolant INSIDE the car's reservoir.


Here's the container we used.


If you plan to use the coolant later, a coolant container or something similar works best. If not, you just need to make sure you can hold it with one hand while siphoning out the coolant (do make sure to dispose of it properly!). We happened to have a coolant container with us, but any sealable container of good quality will do the job.

Note: Take utmost care to ensure that no coolant comes into contact with your skin.

How to extract the coolant: It's best to do this on a cold engine. If that's not possible for any reason, wait for at least 15 minutes before very slowly unscrewing the cap of the coolant reservoir.

Unscrew the coolant reservoir cap and carefully insert the dispenser pump into the coolant. Then, hold your container in a way that lets the coolant fall from the pump straight into the mouth of the container without any spills. A spill in the engine compartment can cause damage, especially if you're doing this on an engine that hasn't fully cooled down, while a spill on the paint can damage the clear coat (and more if it's left unattended).

Pictures are worth a thousand words, so here's what I mean:



Continue pumping until the coolant level is as per your owner's manual's specifications (between the MAX and MIN markings on a cold engine in our case). And then, you're done! Put the reservoir cap back on and screw it tightly. Wash your hands thoroughly after you're done.

It was difficult to get a clear picture of the reservoir in our basement, so I hope this comparison from the side helps.

This was the coolant level before. Note how it's far above the line of the MAX mark.




And here's how the coolant level should be.


Like I mentioned earlier, be careful if you choose to dispose of the coolant. It's best to find a place that takes in hazardous waste, or to give it to a friendly neighbourhood garage that you know will dispose of it properly.

I hope this little thread will be useful for any other victims of aftersales service incompetence or of unintentional overfills while changing coolant themselves. Cheers!

[Aditya]

Thread moved out from the Assembly Line. Thanks for sharing!

[dhanushs]

This, or you should have a drain nut on your radiator, which should reduce the levels.

[sagarpadaki]

I hope you have retained the siphoned off excess coolant. You may need it!

The reason why many service centers top up the coolant tank above the max mark after a coolant change is to account for purging of air pockets in the cooling system as the car undergoes the heating-cooling cycles. The service centers do not have the time or patient to let the car heat up and purge all the air pockets in the cooling system. They purge major air blocks and finish the job. The excess coolant is supposed to fill the void created by the subsequent purging of the air in the coolant circuit, especially the air pockets in the heater core area, which do take multiple heating cooling cycles to push all the air pockets out.

[GForceEnjoyer]

Originally Posted by dhanushs

This, or you should have a drain nut on your radiator, which should reduce the levels.

Yes, true. Unfortunately, we lacked a container that could catch the drained coolant that could also fit under the car for the job. Moreover, this method was a bit easier as a DIY under a time crunch (the car needed to be driven soon), especially considering that the drain plug here is a bit difficult to access when the car is on the ground.

Originally Posted by sagarpadaki

The excess coolant is supposed to fill the void created by the subsequent purging of the air in the coolant circuit, especially the air pockets in the heater core area, which do take multiple heating cooling cycles to push all the air pockets out.

Interesting. I was not aware of this, thanks a lot. I'll be keeping a watch on the coolant level. We do still have the removed coolant with us.

However, is it okay to fill the reservoir so much above MAX that the coolant level on a cold engine reaches the upper coolant hose as was the case here? Couldn't that cause problems once the engine warms up and the coolant expands?

[sagarpadaki]

Originally Posted by GForceEnjoyer

Interesting. I was not aware of this, thanks a lot. I'll be keeping a watch on the coolant level. We do still have the removed coolant with us.

However, is it okay to fill the reservoir so much above MAX that the coolant level on a cold engine reaches the upper coolant hose as was the case here? Couldn't that cause problems once the engine warms up and the coolant expands?

As long as there is some space in the coolant expansion chamber when the engine is hot, there should not be an issue.

[NomadSK]

Originally Posted by GForceEnjoyer

Now here's why this thread exists: once we got the car back from the authorised dealer, I was horrified to see that the coolant level in the reservoir was far above maximum! A serious lapse in workmanship as well as quality control. The service experience this time (and the last few times too) was also underwhelming at best, which is why my dad and I decided to take matters into our own hands, removing the excess coolant at home.

Let me explain why it's not very important;

The coolant in the reservoir is under atmospheric conditions, unless you have expansion collection tank, which you don't have, plastic cap is the indication.

Now, the coolant in the radiator works in a closed loop system and under pressure. This flow of coolant keeps the engine block in the appropriate temperature for best efficiency. This might take you back to your high school chemistry class, but things expand when they get hot. When it comes to coolant specifically, it also creates steam and gas pressure that needs to go somewhere. So there's a 2 way valve at the radiator cap (spring loaded pressure release valve), which is pressure rated cap and when the coolant gets hot enough exerting enough pressure at the radiator cap, it drains to the overflow tank, in hot condition, which just holds the coolant at atmospheric pressure conditions. The hot coolant is transferred back and forth between the tank depending on the pressure exerted from the hot coolant in the radiator.

Once the vehicle cools down, the pressures naturally want to equalize/stabilize. This lower pressure creates a vacuum in the radiator and pulls the coolant from the overflow tank back into the cooling system/radiator and creates a balance. That's why you have a pipe inside the overflow reservior tank (Constantly dipped in the coolant, now you know why min level is important there) to suck back the liquid into the radiator, if not the radiator will suck the air from the available space.

Earlier this hot coolant would just be vented to the atmosphere (the ground to be precise), but in the spirit of environment friendly and keeping our one earth intact, car makers designed tanks to catch and reuse this expanding coolant. The end result was overflow tank.

Having said all of that, the only concern you will have if the coolant in the reservoir tank is above max level, will be the environment, as there will be overflow pipe attached to this reservoir too, which will make the coolant drip down in case additional coolant flows from the radiator to over-flow tank in hot condition.

I hope I didn't confuse you.

[KA20NexonEV]

Another way of removing air pockets from the coolant circuit is to park your vehicle on an inclined slope with radiator at the higher level and then opening the radiator cap and running the engine for some time until the coolant starts to level up to the top of the radiator cap due to thermal expansion. Make sure the AC is on the heating mode. Then close the radiator cap with caution as the coolant will be hot . Park the car again on a level surface and after the engine cools, top up the coolant in the reservoir to the correct level. If you have a rear AC on your vehicle you need to make sure that both the front and the rear AC's are on heating mode while you carry out this exercise. This helps to remove the air pockets from the heater coils.

You can verify if your radiator is having air pockets by opening the radiator cap when the engine is cold. If the coolant is up to the level of overflow hose of the radiator, then it is confirmed that there are no air pockets. If not you will have to top up the radiator first.

Please note that the radiator cap in most of the American vehicles is concealed and not easily accessible unless the top plastic cover is removed. The coolant from the reservoir will not be sucked into the radiator if there is air present inside the radiator.

Care should be taken not to spill the coolant on the floor, as pets might start licking it due to its sweet smell. It will damage the internal organs of the pest if they do so.

[Jeroen]

As other members pointed out, filling over the max is a not uncommon practice to allow for any air in the system to purge.

It’s hardly ever the radiator that is the problem. It’s usually parts of the engine, sometimes the coolant pump and or the heater core. So when refilling a coolant system, always open up the heater control fully. On modern cars with electronic climate control this is often not possible!

On my Jaguar it is impossible to open the heater control valve manually. It’s thermostatically controlled. So it will only start to open with the coolant above a certain temperature.

So after a Jaguar service, they will give you a 1l bottle of coolant and they will tell you you will get a low level coolant alarm after driving some 20 minutes with the heater on.

Sure enough, you will need that 1l of coolant!

These days rare, but coolant pumps used to have bleed valves. My Alfa and my Mercedes do.

These days on most cars the official procedure for refilling a coolant system is with a vacuum filler. It’s a tool that draws a vacuum on the complete coolant system, so the coolant gets everywhere without air pockets. Except for those pesky heater cores!

Jeroen

[puneetakhouri]

Originally Posted by GForceEnjoyer

Now here's why this thread exists: once we got the car back from the authorised dealer, I was horrified to see that the coolant level in the reservoir was far above maximum! A serious lapse in workmanship as well as quality control. The service experience this time (and the last few times too) was also underwhelming at best, which is why my dad and I decided to take matters into our own hands, removing the excess coolant at home.

The overfilling is done to account for air pockets. I recently got the coolant in my Safari Storme replaced from a local FNG, they do not fill the coolant beyond the max level of the coolant reservoir but told me to keep checking the coolant level for at least a week when engine is cold. And when I would check it once a week, I would see the coolant level has gone down to half tank which I topped up. Then next week the same thing, it is only after 3 weeks that the coolant level stabilise.

So the point is that workshops overfill the coolant in the tank for a reason after a coolant change. Since yours was a basic coolant change, hence once the air pocket is consumed, the coolant should level up.

[bkc]

Originally Posted by GForceEnjoyer

Our 2006 Ford Fiesta 1.6 petrol recently overheated in traffic due to a stroke of terrible luck: a coolant leak as well as a cooling fan failure.

You can use a kerosene pump, it comes handy in variety of works.

https://amzn.in/d/aYDgnsQ

[RGK]

Originally Posted by bkc

You can use a kerosene pump, it comes handy in variety of works.

Originally Posted by GForceEnjoyer

which is why my dad and I decided to take matters into our own hands, removing the excess coolant at home.

Another simple way is one can use a 100ml veterinary syringe.

[GForceEnjoyer]

Thanks a lot for the valuable inputs and information, everyone. I greatly appreciate the amount of detail in your responses. Learnt quite a lot.

I'll definitely be keeping a watch on the coolant level for the next couple of weeks (it's normal as of now).

[venukrithish]

Doesn't the coolant reservoir have a relief hose? Excess coolant would just leak out and come to the right level.