gudboy

Hi guys, I'd recently bought a 2003 Nissan Maxima V6 ,3.0 with GCC specifications. I was facing overheating issue with it recently.. Hence took it to the Nissan service station where they have asked me to replace the thermostat and the radiator.. got it replaced recently..

Even after the replacement I have noticed the temperature climbing up to the half mark on the temperature gauge.

The following are the things I have noticed while the temperature goes up-
i. I have noticed huge amount of coolant filling in to the reservoir when hot.
ii. Small small bubbles found inside the reservoir while the coolant fills in.
iii. This mostly happens while driving above 120Kmph at high speeds.

While driving at low speed everything seems normal.. But while driving at high speeds for more time , i have noticed the temperature climbing up around half and sometimes more than that. Is this normal?
Below is the pic i have taken while at high speed.




Please advice guys..

MaxinO2

iTrader: (1)

2003 with a 3.0?

gudboy

Yes.. it is a Gulf Specification.. 2003 model , 3.0

T_Behr904

How hot of a day is it when your temperature gauge goes up? If it doesn't go any higher you should be ok. However, you could still have some air trapped in the coolant system.

gudboy

Thanks for the reply.. This was taken during the afternoon time , around 43*C (109.4 F )...

After the replacement of the thermostat and radiator , i went back to the Nissan service station, and they said that the issue could be from the head gasket and they quoted for engine pull down to check what the exact issue is..

Then after hearing this i really got so much worried.. My friend suggested me to a local garage where the mechanic said that the temperature is normal.. nothing to worry.. i am totally confused.

Guys , i need your valuable suggestions

gudboy

I can see lots of bubbles in the reservoir tank while the temperature is around the half and low range.., but no white smoke coming out from the silencer.. also no signs of coolant mixing with oil ( verified by opening the oil cap)

T_Behr904

Almost 110F is pretty hot. Here where I live it is usually in the mid 90's during the summer with occasional days of 100 to 105 at the highest. On those hot days my temp gauge will go a little over half, but it's still within the normal range.

If you are still seeing bubbles going into the overflow tank then there is still air in the coolant system. When the car is cool, remove the radiator cap and check to see if it is full. Have the car on flat ground or have the front of the car slightly elevated. Top off the coolant if it needs more.

gudboy

Thanks a lot for the reply..

I have checked it during the morning times before starting up the engine.. Coolant shows almost full in the radiator.. and the coolant in the reservoir around the max level... I believe there is no leakage happening..

Once on drive i have seen the overflow tank accumulating the coolant and it even reaches near to the top region of the overflow tank... once the car is stopped , the coolant from the reservoir goes back to the radiator.. seems normal..

I had asked regarding the bubbles to the mechanic at the nissan service station who said that this might be the compression leak coming from the head gasket... compression gas mixing with coolant... and this is a serious issue.. :S

I am totally worried about the situation..

T_Behr904

That is a possibility. If you could get video of these bubbles and post it up that would help.

gudboy

I would post it tomorrow..

gudboy

Have u ever faced similar issues with ur maxima, like the overflow reservoir filling up?

T_Behr904

The coolant level does go up and down depending on driving conditions, that's why there is a full level for hot and full level for cold, but no it has never filled up.

ChrisMan287

iTrader: (34)

Maybe you have air in your system.

T_Behr904

Air does make bubbles

5th gen junkie

iTrader: (1)

i read all the replys ^ wht u need to do is remove the rad cap cheack if u see coolant full in the rad if ur low on coolant add some first then turn the car on and turn the heater on high and let it run for like 30 mins tht will get rid of all ur air bubbles then check if its still over heating if so then u gotta replace ur coolant temp sensor witch is on ur driver side cooling line this should fixes ur problem wish u well...

DjHackStyle

+1

you must bleed the air out of the radiator, when the car is cold and on flat ground, take the radiator cap off and turn the car on and look on the passenger side of the radiator on the bottom there is a hose becareful with the fans and stuff and grab that hose and keep squeezing it you should see bubbles coming out of the radiator, if you dont see anymore bubbles then fill up the radiator to the tip top with antifreeze and put the cap on it tight, you might spill a little coolant just clean it up dont worry.

another thing is make sure you have an original Nissan thermostat, the aftermarket ones will keep your fans running all the time once it warms up and it will still overheat. a quick way to check this is to touch the thermostat metal housing and see if its cool when the car is overheating, that would the thermostat is not letting the coolant out fast enough (no good)

gudboy

Thanks a lot for all ur replys..

gudboy

^The thermostat is original and was fixed by the nissan service station people. to be frank I am really not satisfied with their service.. They really dont have any answer to my questions.. All they say is replace this , that etc.. now they want me to pull out the engine and check for head gasket leaks/ head bend which they say could be the problem of air bubbles ( combustion gas mixing to the coolant)..

gudboy

I will do the same of bleeding the air out as advised by you guys and will reply you all with the feedback... thanks a lot once again for all your time..

DennisMik

iTrader: (2)

Setting the heater temp to high has the same effect as setting it to off. There is no water valve on the heater core - water flows through it all the time. The 1994 Maxima was the last year to have a heater core water valve. The temperature inside the car is controlled by directing the air through the heater core or around it.

Seeing bubbles in the reservoir tank is not normal. I would have the cooling system pressure checked and see if the system holds the pressure.

gudboy

Seeing bubbles in the reservoir tank is not normal. I would have the cooling system pressure checked and see if the system holds the pressure.[/QUOTE]

^The pressure check should be done after the engine is hot or when the engine is off..?

I had given the car at nissan service station and as per them they had done the pressure and combustion test and said they did'nt find any issues.. But frankly speaking they are not much experienced people.. all they say is change this, change that...

the following have been done until now-
i. Radiator cap replaced (original from nissan)
ii. Complete Radiator (original from nissan)
iii. Thermostat (original from nissan)
iv. flushing with original good quality coolant.

Haven't yet tried bleeding the air out of the radiator yet... will do it this evening and let you guys know..

I just had a test drive now for around 30kms(18.6 miles) at a maximum speed of not exceeding 100kmph (62miles).. things are normal.. temperature shows less than the half mark .. no heating observed.. but when opening up the hood, there is still small bubbles oozing out in to the reservoir tank..

gudboy

Does anybody think its the head gasket leak causing these bubbles?

T_Behr904

It's possible. Get a pressure check as mentioned. That will reveal it.

gudboy

Guys, I have done the bleeding of air from the radiator. Seems kinda dangerous...

Kept the engine idle for around 10minutes,

Please check this video - http://www.youtube.com/watch?v=Qs1SU...ature=youtu.be or http://youtu.be/Qs1SUQfSVhc


Bubbles were coming out at regular intervals, but the temperature gauge was showing normal temperature (quarter mark)

I noticed the green coloured coolant turning kinda milky with foam,
Check out this video-
http://youtu.be/-tDOLCHuLl0


Guys please suggest , wat needs to be done next...

ChrisMan287

iTrader: (34)

Why are you revving up the motor?

DennisMik

iTrader: (2)

The pressure test is done with the engine off. The engine can be cool or hot, it does not matter. Allow the pressure testing to run at least a half hour, longer if you can. If everything is ok, the cooling system will not lose any pressure.

I watched your videos and I do not like what I saw. I am thinking that you might have a blown head gasket.

DjHackStyle

Watched ur videos ur right it looks scary, i bled my radiator and i didnt see bubbles like that. Consult another shop for a 2nd opnion and take it from there.

Toxic!

iTrader: (3)

I doubt this is the cause for the bubbles but you might want to pressure check your radiator just to make sure there are no cracks anywhere. I had the slightest crack by where the radiator cap goes and my car overheated cause of it. I replaced the radiator and it went away. Best of luck

gudboy

I have been cheated by the previous owner for sure..

The cost for the head gasket repair is too high ryte?

Is there any other easy fix for such head gasket issues? I have seen many posts online recommending on some sealants... Will the use of these sealants fix the head gasket leaks?


Thanks a lot once again for your valuable suggestions and opinions

ShocknAwe

iTrader: (3)

It isnt air or else the coolant level would drop and it is not correct? Check your oil for coolant and you will know if you have a blown head gasket. The temp sensors on the car are for water and are not accurate. It only tells you if it is in the right range and if the temp gets that high above normal then you have a problem. You could have a cracked radiator but due to the milky appearance of the coolant I am leaning towards a Blown HG. Sorry

gudboy

^ I have checked the oil cap and it shows no signs of coolant mixture... also i have checked for white smoke from the silencer, couldn't find any...Its clean smoke...

Is there any problem if i continue driving under current situation? will the head gasket leak affect any other parts? please advice..

DennisMik

iTrader: (2)

A blown head gasket will only get worse if you continue to drive the car. Bubbles in the coolant means the gasket has failed between a cylinder and a coolant passage. Eventually the leak will allow the coolant to go into the cylinder, and you will have to be adding coolant all the time.

I had a car with a blown head gasket and I continued to drive it. It got so bad that I had to add water every time I started the car - in the morning going to work and in the evening coming home from work. When I finally replaced the head gasket, I discovered that the surface of the engine block where the leak was at was no longer smooth and flat. A new gasket could not seal the leak. I had to have the engine block surface milled flat again.

Max_5gen

iTrader: (2)

with your outside temperature I'm not surprised you have those bubbles. 'I think' what you observe is normal and I'd also suggest that you had bad radiator cap initially. Rad cap has a valve which maintains cooling system under 10 psi pressure. This pressure increases boiling temperature of the coolant (by ~40 F) preventing it from boiling. If that valve was bad and had a leak it would lead to 2 effects you originally observed- filling overflow tank and boiling bubbles. These bubbles would lead to decrease of efficiency of your cooling system.

If I'm reading your post #21 correctly you don't observe drastic changes in coolant level after cap replacement and your temp seems back to below the middle. If so, I'd call it a fix and wouldn't worry much anymore.

Checking for bubbles on the hot engine with cap removed doesn't allow system to get under necessary pressure and you might simply observe coolant boiling, not the air coming out of the system or exhaust gasses. I'd stop doing this if I were you.

gudboy

Thanks a lot guys for ur valuable opinions.. I will be visiting one of my friend's friend garage tomorrow for a third opinion regarding the problem..

I read online that some sealants could help if it was a head gasket leak..

http://www.k-seal.co.uk/
http://www.steelseal.co.uk/

Have anyone tried using theses sealants? will this help if my case was a head gasket leak?