Coolant level going down

[Sash1401]

Fellow bros,

I'm current driving an avante. Just went for servicing on sat n I did the following.

Basic servicing(engine oil and filter changed)
Coolant changed
Brake oil changed
Spark plug replaced
Atf oil changed

After the servicing, drove out wif family to spend our weekend. Sun went JB n as usual stuck in the jam as well. Mon when I checked the car, found out that the coolant in the secondary tank dropped closed to half. Opened up the radiator and found the coolant level Oso dropped. So I top up wif water for both side and drove off... For the next 2 days, the level at the radiator dropped but the level at the secondary tank remains the same. So I drove bk to the ws today.

They tested and jacked up the car n no leakage was found. They came to a conclusion that during the time when they topped up the coolant, it's actually not full yet so the level will tends to drop and it will stablised once the coolant is really full.... I've decided to take a few more days to monitor, but is there any truth in wat they said? Considering the fact that during the weekend I've drove a lot and the coolant shld haf stablised till then...

[skboy]

It happened to my Sonata before. Mechanic changed the radiator cap and problem solved. Sometimes small leak cannot be detected. Just watch the water level and gauge these two days.

 

Fellow bros,

 

I'm current driving an avante. Just went for servicing on sat n I did the following.

 

Basic servicing(engine oil and filter changed)

Coolant changed

Brake oil changed

Spark plug replaced

Atf oil changed

 

After the servicing, drove out wif family to spend our weekend. Sun went JB n as usual stuck in the jam as well. Mon when I checked the car, found out that the coolant in the secondary tank dropped closed to half. Opened up the radiator and found the coolant level Oso dropped. So I top up wif water for both side and drove off... For the next 2 days, the level at the radiator dropped but the level at the secondary tank remains the same. So I drove bk to the ws today.

 

They tested and jacked up the car n no leakage was found. They came to a conclusion that during the time when they topped up the coolant, it's actually not full yet so the level will tends to drop and it will stablised once the coolant is really full.... I've decided to take a few more days to monitor, but is there any truth in wat they said? Considering the fact that during the weekend I've drove a lot and the coolant shld haf stablised till then...

[Sash1401]

 

It happened to my Sonata before. Mechanic changed the radiator cap and problem solved. Sometimes small leak cannot be detected. Just watch the water level and gauge these two days.

 

Bro can i noe hw much does the radiator cap cost?

[ER-3682]

Maybe there is an "Airlock" during filling of coolant....change the cap first...& monitor...cap should be quite cheap..between $10-$20.

[Yuan]

 

It happened to my Sonata before. Mechanic changed the radiator cap and problem solved. Sometimes small leak cannot be detected. Just watch the water level and gauge these two days.

 

Bro can i noe hw much does the radiator cap cost?

 

I drive a VW and had similar problems as yours.

 

Checked and there was no leakage. Discovered that it was a faulty coolant cap as there were vapour and coolant water around the cap and tip of the coolant bottle.

 

Changed the cap and it cost me around S$25 dollars.

[Shando]

Most likely it's the radiator cap. You just need to monitor it and see if it stabilise.

[cmdsea]

Best case: Airlock on refill. solved already... (quite plausible as coolant just changed)

 

Minor case: Radiator cap seal perished... (remove cap and have a look at the black gasket inside. if the rubber is cracked or has deep indentations then change it as a precaution anyway) Autobacs will sell.. Maybe $5.?

 

Worst case: Head gasket leak... unlikely on something as new as an Avante unless you have massively overheated the engine at some point..

[13177]

Seems like based on the post here, only happen to Korean car?

[Shando]

Seems like based on the post here, only happen to Korean car?

 

Airlock or spoilt radiator cap can happen to Korean, Japanese or Conti car. Just need to monitor and the problem will be solved in a matter of time.

[skboy]

Hi TS

 

Radiator cap is the most ideal component you should change first. Unless leak is spotted somewhere else. For Korean and Jap cars, the radiator cap should cost you around $10.

 

Monitor your  gauge closely especially when you're always queuing on the causeway. When the gauge reading passes your usual mark, something likely is wrong. For my Sonata, it always stay at 2mm below centre mark.

 

Always carry 3 litres of water in your trunk as spare if you're a frequent Johor traveller. If there's no major burst, this water can help you with some distance.

[Toe_toe7]

Should be air lock..you just need to monitor for the next few days..it should not drop again..

[Kklim]

Modern cars don't have a valve/cock to purge air from the coolant system so air trapped in the hoses and elsewhere cannot be burped.

[Wildaltum]

Hi TS, can go to car accessories shop or some petrol kiosks to buy the radiator cap.  If your radiator cap is worn out, the high pressure from the heated coolant travelling the radiator will evaporate out and that is usually the cause of the drop in coolant level if there are no other leakages found.  Please buy the correct size cap..there should be a number 1.8 or 2.0 etc printed on your original radiator cap.  Wrong size will cause more drop in coolant level.

 

Rgds

[Sash1401]

Dear fellow bros,

 

Thank u so much for the valuable advises. I think i will monitor for thr next few days to c if the level stablised. Meanwhile i will go get the radiator cap to change as well. I do hope its becoz of the air lock n the water level will remains the same after a few more days.

[Yeobh]

Modern cars don't have a valve/cock to purge air from the coolant system so air trapped in the hoses and elsewhere cannot be burped.

 

You can remove the air bubbles via a simple coolant filling  or a vacuum gun. Have not come across any shop in Singapore using the simple coolant filling device or the more expensive vacuum gun

 

[Blueblueman]

Seems logical. Happened to me once on a lancer too.

Just replaced the cap. Afew dollars only.

 

Monitor the water level, if just one off should be fine.

 

Beware if it's a subaru, driving one for 2 years.

Radiator issue min 2-3 times

[Kb27]

Fellow bros,

 

I'm current driving an avante. Just went for servicing on sat n I did the following.

 

Basic servicing(engine oil and filter changed)

Coolant changed

Brake oil changed

Spark plug replaced

Atf oil changed

 

After the servicing, drove out wif family to spend our weekend. Sun went JB n as usual stuck in the jam as well. Mon when I checked the car, found out that the coolant in the secondary tank dropped closed to half. Opened up the radiator and found the coolant level Oso dropped. So I top up wif water for both side and drove off... For the next 2 days, the level at the radiator dropped but the level at the secondary tank remains the same. So I drove bk to the ws today.

 

They tested and jacked up the car n no leakage was found. They came to a conclusion that during the time when they topped up the coolant, it's actually not full yet so the level will tends to drop and it will stablised once the coolant is really full.... I've decided to take a few more days to monitor, but is there any truth in wat they said? Considering the fact that during the weekend I've drove a lot and the coolant shld haf stablised till then...

 

After coolant change, there will be air bubbles trapped inside the radiator (cooling system).

The mech should purge the air bubbles as much as possible.

With the radiator cap unplugged, air bubbles can escape to the top, otherwise it will be trapped inside the cooling system and circulate about.

 

Minor drop in coolant in radiator can be expected and should stablilize after majority of the air bubbles are purged. It may take a few days.

If not stabilized, there might be a leak somewhere.

 

Radiator cap function is to seal and pressurized the system.

Any overpressure will release the coolant to the overflow (plastic) tank outside.

Any lack of coolant (vacuum) should pull it back from the overflow tank into the radiator.

 

So usually, I'll check the overflow tank. If it's empty, most likely the coolant in the radiator is low.

If it's full at the correct level, it's unlikely the coolant in the radiator is low, unless the cap is not functioning normally.

It has a rubber seal, that tends to degrade after a while.

 

It cost about $10+ at parts dealers and easily changed by yourself.

Just wait for the engine to ccol down.push and rotate the cap anticlockwise until it lock, then pull it up straight.

Installation is the reverse. Find the catch position, push down and rotate clockwise until it lock.

[Sash1401]

Thanks bro!! Dis is indeed v detailed

After coolant change, there will be air bubbles trapped inside the radiator (cooling system).

The mech should purge the air bubbles as much as possible.

With the radiator cap unplugged, air bubbles can escape to the top, otherwise it will be trapped inside the cooling system and circulate about.

 

Minor drop in coolant in radiator can be expected and should stablilize after majority of the air bubbles are purged. It may take a few days.

If not stabilized, there might be a leak somewhere.

 

Radiator cap function is to seal and pressurized the system.

Any overpressure will release the coolant to the overflow (plastic) tank outside.

Any lack of coolant (vacuum) should pull it back from the overflow tank into the radiator.

 

So usually, I'll check the overflow tank. If it's empty, most likely the coolant in the radiator is low.

If it's full at the correct level, it's unlikely the coolant in the radiator is low, unless the cap is not functioning normally.

It has a rubber seal, that tends to degrade after a while.

 

It cost about $10+ at parts dealers and easily changed by yourself.

Just wait for the engine to ccol down.push and rotate the cap anticlockwise until it lock, then pull it up straight.

Installation is the reverse. Find the catch position, push down and rotate clockwise until it lock.