Jump to content

Kia Cerato Variant 2 persistent overheating issue


Zexel
 Share

Recommended Posts

the previous workshop did not do a full check when they change the radiator? 

usually they will run the engine for 10~20min to make sure there are no over-heat issues...

↡ Advertisement
Link to post
Share on other sites

Supersonic

Is your car losing coolant ?

 

I had quite a few bad experience with overheating.

 

1. First was a oil cooler broke. It mix engine oil with coolant.

That was bad, the cooler was subsequently bypassed.

2. Then radiator leaked and was replaced.

3. Thermostat was changed a couple of times.

4. Pressure cap broke.

5. New radiator leaked again after one year.

6. Hose leaked due to vibration and got cut.

 

But everytime, it overheat it's always a lack of coolant, that had drained off somewhere.

Link to post
Share on other sites

the previous workshop did not do a full check when they change the radiator?

usually they will run the engine for 10~20min to make sure there are no over-heat issues...

Yes they do actually! Just that the temperature didnt creep up then. Its after driving for sometimes n idling, then the issue surface :(

Is your car losing coolant ?

 

I had quite a few bad experience with overheating.

 

1. First was a oil cooler broke. It mix engine oil with coolant.

That was bad, the cooler was subsequently bypassed.

2. Then radiator leaked and was replaced.

3. Thermostat was changed a couple of times.

4. Pressure cap broke.

5. New radiator leaked again after one year.

6. Hose leaked due to vibration and got cut.

 

But everytime, it overheat it's always a lack of coolant, that had drained off somewhere.

Wow im sure u went thru alot of headache n heartache -.-

 

Nt too sure yet bro, as just collected thr car ytd, will check when im driving later!

 

Urs sounds like gasket leak, or cracked block :/

Link to post
Share on other sites

Twincharged

Might be engine block crack. If you have changed the whole cooling system and it is installed properly. Since its a second hand car, check if previous owner maintain properly or not. I had a friend whose car always overheat. Found out it is a crack in the engine block. 

Link to post
Share on other sites

Supersonic

Yes they do actually! Just that the temperature didnt creep up then. Its after driving for sometimes n idling, then the issue surface :(

Wow im sure u went thru alot of headache n heartache -.-

 

Nt too sure yet bro, as just collected thr car ytd, will check when im driving later!

 

Urs sounds like gasket leak, or cracked block :/

 

Check your tailpipe.

Is it emitting white smoke ?

White smoke comes from the coolant, which would indicate head gasket leak.

 

When the temp creeps up, it's a few things.

1. water pump not working properly

2. hoses or radiator is blocked

3. radiator fan for engine not working, this radiator may be separate and different from aircon.

4. thermostat remains closed and blocked coolant flow

5. very little or no coolant due to leak

Link to post
Share on other sites

Hi All,

 

i had recently purchased a 'new' 08 kia cerato variant 2, intending it to service my needs of ferrying my family and kiddo around.

 

Everything seems well and fine, until i went for a fan belt, water pump change 2 weeks later, as i want the car to be in perfect running condition.

 

After the change, things starts going haywire.. the car temperature gauge starts to creep up past 1/2 point mark, till 3/4 to 'Hot'.

This happened when i drove the car for some time (30 mins or so?) and when the car is idling either from traffic lights, or parked in the parking lot.

 

Rev-ing the car in neutral, or moving off will result in temperature dropping.

 

Fan is spinning when aircon is on, fan is spinning when aircon is off as well, hence mech said its isnt the issue.

 

Went back to garage the next day, was advised to changed out radiator and refresh a few hoses, as the radiator were kinda chocked with, and it even choked several hoses as well. Thermostat had been removed as well -.-

 

Sadly, after doing all the changes, the issue still persist.

 

Noticed during the testing of car after installation done, air bubbles were present in the coolant reserve tank. Mech said most likely head gasket is gone as well.

 

Curious any bro or sis or gurus had any similar experiences on this? how much roughly will the repair cost be this time? Sigh :/

 

Thanks!

 

Dunno leh. It sounds like the thermostat is stuck in the closed position.

When you start your car cold the thermostat is closed and stop the coolant from entering the engine so as to warm up the engine. Once the engine optimal temperature is reached the thermostat would open and the coolant would circulate. That's how it works.

 

You mentioned at idle the temperature would rise and would drop when you rev the engine. The thermostat would probably be stuck in closed during idling.

 

Did the mechanic replace the thermostat?

 

As for the bubbling coolant there's a possibility there's a leak and air is entering the cooling system. Need to find the leak and plug it.

 

Edited by Watwheels
Link to post
Share on other sites

I feel it's a case of incompetent mechanic at work. I suggest u go to another workshop to get it checked. If you need a good and honest workshop just pm me. There is no air con lounge though. Haha

  • Praise 1
Link to post
Share on other sites

Not sure why you initiate water pump change at the first place if there is no leak, but if everything is well before change, then it is simply dumb mechanic never bleed the air after coolant change. That is why you see bubble. Cracked head gasket or block will always give problem even before the change of pump.

Link to post
Share on other sites

Might be engine block crack. If you have changed the whole cooling system and it is installed properly. Since its a second hand car, check if previous owner maintain properly or not. I had a friend whose car always overheat. Found out it is a crack in the engine block.

That could be cause or effect of overheating. More likely effect of overheating. There should be something else wrong with the cooling system resulting in the overheating and frequent overexpansion and contraction of the engine block leading to metal fatigue and cracking.
Link to post
Share on other sites

Might be engine block crack. If you have changed the whole cooling system and it is installed properly. Since its a second hand car, check if previous owner maintain properly or not. I had a friend whose car always overheat. Found out it is a crack in the engine block. 

 

oh mine... i dun dare to imagine the repair cost

Link to post
Share on other sites

(edited)

Check your tailpipe.

Is it emitting white smoke ?

White smoke comes from the coolant, which would indicate head gasket leak.

 

When the temp creeps up, it's a few things.

1. water pump not working properly

2. hoses or radiator is blocked

3. radiator fan for engine not working, this radiator may be separate and different from aircon.

4. thermostat remains closed and blocked coolant flow

5. very little or no coolant due to leak

 

seems like theres no white smoke,

 

check coolant reserve today, the level seems to drop quite a bit.

 

radiator coolant lvl, nt filled to the brim, but can still see with naked eyes :/

 

engine oil color.. still consider blackish.. not milky or kopi color.

 

Start car with radiator cap off, can see foam foaming, abit of smoke. drove to work, 25 mins journey, temperature stable for now.. well, not much idling tho so cnanot tell :(

Dunno leh. It sounds like the thermostat is stuck in the closed position.

When you start your car cold the thermostat is closed and stop the coolant from entering the engine so as to warm up the engine. Once the engine optimal temperature is reached the thermostat would open and the coolant would circulate. That's how it works.

 

You mentioned at idle the temperature would rise and would drop when you rev the engine. The thermostat would probably be stuck in closed during idling.

 

Did the mechanic replace the thermostat?

 

As for the bubbling coolant there's a possibility there's a leak and air is entering the cooling system. Need to find the leak and plug it.

 

 

mech mentioned that the previous owner mech cut away the thermostat.

 

So practically, my car dun have thermostat.

I feel it's a case of incompetent mechanic at work. I suggest u go to another workshop to get it checked. If you need a good and honest workshop just pm me. There is no air con lounge though. Haha

 

pmed you!

Not sure why you initiate water pump change at the first place if there is no leak, but if everything is well before change, then it is simply dumb mechanic never bleed the air after coolant change. That is why you see bubble. Cracked head gasket or block will always give problem even before the change of pump.

 

its a routine change out, coz i just colllected this car 3 weeeks plus ago. want to make sure everything is in tip top condition :(

 

you had a point here.. theres no overheating of sort of before change

 

 

 

 

Update:

 

check coolant reserve today, the level seems to drop quite a bit.

 

radiator coolant lvl, nt filled to the brim, but can still see with naked eyes.

 

engine oil color.. still consider blackish.. not milky or kopi color.

 

Start car with radiator cap off, can see foam foaming, abit of smoke. drove to work, 25 mins journey, temperature stable for now.. well, not much idling tho so cnanot tell :(

 

ws boss promised to investigate and get back to me soonest. well

Edited by Zexel
Link to post
Share on other sites

why do you open the radiator cap?

 

cooling-system-for-ic-engines-18-638.jpg

I am suspecting that without the low pressure that is allowed to build up, the boiling and bubbling point is lowered?

 

  • Praise 1
Link to post
Share on other sites

http://www.tuneruniversity.com/blog/2011/06/beating-the-heat-advantage-of-a-high-pressure-radiator-cap/

 

 

A Little Technical Background

To understand why the higher pressure radiator caps might be useful, we first need to understand something about the fluid inside the cooling system.

In an ideal world, engines would be cooled by straight water with no antifreeze added. Water is an excellent cooling agent and is extremely efficient at carrying heat away from the engine and then exchanging that heat with the air via the radiator.

However, water has a few properties that make it imperfect as an automotive coolant. For one, it has a relatively high freezing temperature at 32 degrees Fahrenheit. Freezing would be bad enough but water also has the unique property that it expands at its freezing (which if you've ever left a soda in the freezer before, you know why that's bad). It also has a relatively low boiling point at 212 degrees Fahrenheit.

Since most engines are operating at a temperature of around 185-205 degrees, that only gives us a small amount of wiggle room before boiling would occur. Boiling is bad for a number of reasons which I won't get too into here, but, steam/bubbles in coolant actually insulate coolant from the combustion chamber and would render the coolant useless at cooling the hot engine. It can also cause water pump failures amongst other damage via a process called cavitation.

Water is corrosive and it will gradually eat away at seals and cause metal inside your engine to deteriorate. Finally, it isn't a very good lubricant and the water pump and seals in your cooling system rely on other compounds in your coolant to provide those properties.

So, we generally add antifreeze to distilled water to create the coolant we run in the car.

Antifreeze both keeps water from freezing in the winter (by lowering the freezing point of the water) and at the same time raises the boiling point of the water. A 50/50 mixture as we typically use actually gives us a freezing point of -35 degrees Fahrenheit and a boiling point of 223.

The trade off for the extra wiggle room of course is that antifreeze is not a very efficient heat exchanging fluid. In fact, 100% antifreeze in your cooling system would be an absolutely terrible idea. When you add antifreeze to water, the ability to cool evenly and quickly drops. Besides that, up until about 60% coolant, you do gain boiling point and freezing point. However, past 60% coolant to water, you start to go the other way again, sharply.

While we'd love to run 100% distilled water in the cooling system, we can't because of corrosion and boiling/freezing points. We also don't want to use 100% antifreeze because it would be a poor cooling fluid. Therefore, we need a compromise, which is usually a 50/50 ratio of the two fluids mixed together.

The Role of Pressure

DSCF0990-150x150.jpgBut, back to the radiator cap. As the coolant gets hot it expands creating pressure in the system. The hotter things get, the more pressure created. The radiator cap allows pressure to build up in the cooling system and will eventually vent that pressure to the overflow bottle as the need arises. The cap does this by a spring loaded valve which serves as a pressure relief valve at a rated pressure. You'll notice that there's a plunger on the bottom of the cap. As pressure builds, it pushes up on that valve until eventually the valve is opened far enough for coolant to flow out of the tube connected at the radiator fill neck. It closes again when the pressure has dropped to the desired level.

This tank is there just to catch the coolant and store it until things cool back down, when a vacuum will be created and most of the coolant will return to the cooling system.

Pressure actually increases the boiling point of a fluid as you may know from high school physics class. The pressure literally forces the liquid to remain a liquid longer and does not allow it to transform into vapor. All modern automotive cooling systems are under pressure, completely regulated by the radiator cap. 1.1 bar is roughly 15psi, and 1.3 bar is around 18psi.

How much does the pressure raise the boiling point? Well, it's about 2-3 degrees for every psi that we increase the pressure of the system. Therefore, by using a 1.1 bar cap we make the average boiling point of a stock cooling system somewhere closer to  around 257-260 degrees.

When we change from a a 1.1 bar to 1.3 bar cap, we gain 0.2 bar or roughly 2.9psi of pressure. So, we effectively get 8.7 degrees (or around that) on top of the 257-260 degrees  before we might experience boiling coolant in the system.

So if some extra pressure is good, why not a lot? Well, it may seem obvious, but the cooling system on your car is rated to a certain pressure. The radiator cap is designed to be the weak point in your cooling system so it can safely vent pressure, you don't want to use a cap that is so resistant to venting pressure that it causes some other part of the system to become the weak point.

 

 

Just a little background info on the role of the radiator cap and why I think you may be artificially inducing the boiling by opening the cap while having the engine running.

 

hope this may help you troubleshoot.

 

 

Link to post
Share on other sites

seems like theres no white smoke,

 

check coolant reserve today, the level seems to drop quite a bit.

 

radiator coolant lvl, nt filled to the brim, but can still see with naked eyes :/

 

engine oil color.. still consider blackish.. not milky or kopi color.

 

Start car with radiator cap off, can see foam foaming, abit of smoke. drove to work, 25 mins journey, temperature stable for now.. well, not much idling tho so cnanot tell :(

 

mech mentioned that the previous owner mech cut away the thermostat.

 

So practically, my car dun have thermostat.

 

pmed you!

 

its a routine change out, coz i just colllected this car 3 weeeks plus ago. want to make sure everything is in tip top condition :(

 

you had a point here.. theres no overheating of sort of before change

 

 

 

 

Update:

 

check coolant reserve today, the level seems to drop quite a bit.

 

radiator coolant lvl, nt filled to the brim, but can still see with naked eyes.

 

engine oil color.. still consider blackish.. not milky or kopi color.

 

Start car with radiator cap off, can see foam foaming, abit of smoke. drove to work, 25 mins journey, temperature stable for now.. well, not much idling tho so cnanot tell :(

 

ws boss promised to investigate and get back to me soonest. well

Coolant reserve drop means there is a leak somewhere.

 

Don't drive already, who knows when you will meet traffic jam and need to accelerate and stop and accelerate, it will speed up heating up. Overheat of engine will need to overhaul if not change whole car. 

 

btw, car will not heat up if you constantly move the car non-stop above 60km/h. The air going thru your vent will cool down the engine and radiator. It will not show symptom of radiator spoil, or fan spoil or whatever spoil. 

Link to post
Share on other sites

Hi All,

 

i had recently purchased a 'new' 08 kia cerato variant 2, intending it to service my needs of ferrying my family and kiddo around.

 

Everything seems well and fine, until i went for a fan belt, water pump change 2 weeks later, as i want the car to be in perfect running condition.

 

After the change, things starts going haywire.. the car temperature gauge starts to creep up past 1/2 point mark, till 3/4 to 'Hot'.

This happened when i drove the car for some time (30 mins or so?) and when the car is idling either from traffic lights, or parked in the parking lot.

 

Rev-ing the car in neutral, or moving off will result in temperature dropping.

 

Fan is spinning when aircon is on, fan is spinning when aircon is off as well, hence mech said its isnt the issue.

 

Went back to garage the next day, was advised to changed out radiator and refresh a few hoses, as the radiator were kinda chocked with, and it even choked several hoses as well. Thermostat had been removed as well -.-

 

Sadly, after doing all the changes, the issue still persist.

 

Noticed during the testing of car after installation done, air bubbles were present in the coolant reserve tank. Mech said most likely head gasket is gone as well.

 

Curious any bro or sis or gurus had any similar experiences on this? how much roughly will the repair cost be this time? Sigh :/

 

Thanks!

 

By any chance, did you purchase a Silver colour SJM22**R OPC variant 2? if so PM me, i know what is the issue.

Link to post
Share on other sites

By any chance, did you purchase a Silver colour SJM22**R OPC variant 2? if so PM me, i know what is the issue.

 

Nope it isnt, its a blue normal plate Variant 2 :(

Link to post
Share on other sites

Nope it isnt, its a blue normal plate Variant 2 :(

 

 

Oh.. scare me. That car was practically junk when we sold it because of overheating issues also.

 

 

I will just share what has happened to that silver variant 2, maybe yours might have the same symptoms and you will know what's wrong.

 

Symptoms:

 

1) Engine overheat randomly while idling

2) When car is moving, no overheat

3) Coolant is at "full mark" but doesn't help

 

My trusted mechanic for 15 years plug in OBD port and check no errors. Replace whatever that has got to do with cooling the engine, radiator cap, fan, belt, thermostat, flush coolant, change EO, triple check for any leaks, change coolant hose. No use.. still same issue.

 

 

My mechanic also scratch head and suspect aircon compressor maybe got fault. i hear liao also stun. But we trust him as all my friend and our family cars he's taking care of the fixing and repair.

 

So he asked his aircon mechanic friend to come by his shop to take a look at our car, aircon mechanic check and check and diagnose it with aircon wiring fault. To prove his point, he off the engine and turn off the aircon switch. He then crank engine and start the engine, after engine start for 10 seconds, he turn on aircon, immediately engine stall (we didn't know this symptom as we always leave the aircon on.)

 

By then we are so tired with fixing this car that we decided to sell it 4 months ago.

 

Don't ask me how come aircon wiring can cause overheat or what, i really don't know. I am telling you based on what was conveyed.

 

I hope the information helps you.

 

Edit: to add in, we also did throttle body cleaning, change sparkies to NGK iridium and new K&N filter. Nothing helps until aircon mechanic diagnose it with wiring fault. And we are the first owner and mileage less than 50k km when we sold it. 

Edited by turtlebroth
↡ Advertisement
Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
 Share

×
×
  • Create New...