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Water radiator is bubbling

Hello guys,

Before two months I had the blastic tank mounted on radiator head leaking so I replaced it then after two weaks The internal heater core leaked. So i Suspect there is something wrong with the car. May be pressure due to head gasget or something else so as you see in the video there is bubbling but I can’t see any trace for mixing oil and water. Any help would be appreciated for diagnosing advices or ideas.

Best regards

Bubbles like that point to a head gasket breach. How does the oil look? Take the fill cap off and see if it has a choclate milk residue on it. That is a sign that coolant is leaking into the oil.

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There is no water trace. The oil looks very good. Just to point that it is started to bubble aftet about 15 min running…when it cold it wasn’t bubbling but once it gets warm the water level start to rise in the bottle and bubbling.

Sometimes the little hose leading from the radiator cap to the overflow bottle can develop a leak, or fail to seal properly at one end or the other, and air gets introduced as coolant flows into the bottle. Then the air bubbles up and you get worried. I’d check that hose first.

If that didn’t pan out then I’d be worried about a head gasket.

That’s a link to a very easy test. You hook the test cylinder up to an engine vacuum source, pour the fluid in it, and then stick the rubber stopper into the radiator fill neck. The vacuum will suck air in from the radiator and if combustion gasses are present (indicates a head gasket breach), the fluid will change from blue to yellow.

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The water level rising in the reservoir after the engine warms up is normal. The bubbles are not.
The bubbles are caused by either air or combustion gasses getting into the system.

IMHO you need to have it looked at. A shop can tell with simple testing whether there’s any trace of hydrocarbon in the coolant. This is often done by what I call a “lab test”, a simple chemical test with a kit that’ll indicate the presence of hydrocarbons. From there the mechanic may want to test the cylinders for their ability to hold air, called a “leakdown test”. An inability to hold air combined with failure of the “lab test” is a sure sign of a headgasket breech.

My recommendation is to get this done ASAP. If you do have a headagasket breech, continuing to operate the engine will manifest itself as further damage.

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I had a problem like that on my camero , could be a head gasket watch for water usage or water in oil , oil in water. It can also be air in the system that needs to be bled out. If you had work done on the cooling system its possible they didnt bleed the air out. But either way i wouldnt drive much till you figure it out, even air in the cooling system can cause some damage from pressure.

The thing about head gaskets that i was told was they dont always bust in a spot that will give water in oil or oil in water. Depending on what side busted you may not have any symptoms or very little till the car dies.So leak down test and combustion gasses check in the coolant. There are chemical test you can do to check for gasses.

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Sorry but that’s about as bad as my diesel ever was. I hobbled it home with the radiator cap off and to the shop for $1200 head gaskets. The higher pressure created leaks in the radiator and heater core. Just IMHO, but does not look good.


The engine has a blown head gasket.



Thank you guys for your advices and valuable info. I will take it to Mechanic tomorrow and return with feed back.

I took it to mechanic…it was Gasget.
Thanks anyone for your help.

That’s very true. The thing right next to the combustion chambers is the water jacket, and the breech will generally be blowthrough from the cylinder combustion. Once the breech occurs, the combustion in the cylinders blows gasses directly into the water jacket.

Oil passages are generally not directly adjacent to the combustion chambers. They’re generally on the other side of the water jacket, keeping them from getting unnecessarily heated up by the cylinders.

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Good for you OP for getting the problem diagnosed. Head gaskets springing a leak are not an uncommon problem reported here. As you’ve probably discovered the fix involves a lot of labor so is pretty expensive, but the up side is that the fix usually takes and returns the engine to good operating condition for many thousands of more miles.

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…or until the next time the engine is operated without coolant.

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True. very true …

@Nevada_545 I never left the engine with low coolant beside my car dosen’t have temperture gauge but instead it has red light which comes on when the engine overheated. Any way, neither low coolant or redlight on in my case. It sounds rare but this is the real strange case experienced by my Nissan versa 2008.

In your original post you stated that the plastic tank on the radiator had failed. Generally when this happens it is realized after the engine has overheated, in your case you may have found the leak before the cooling system became low but if that is the case why look for coolant in the oil if the engine had not been damaged by overheating?

Nevada_545 I suspected the headgasget due to the symptoms of high pressure in the radiator and water passages ( leading to plastic tank and heator core) leaks. High pressure lead me to monitor the radiator with cap off and I saw these bubbles. I hope it is clear for you now .

Head gasket failures and warped cylinder heads are generally the result of operating an engine at very high temperatures, “overheated”.

Each vehicle that is towed in with a destroyed engine due to overheating has an owner that says there were no visible warnings and the engine did not overheat.

Nevada_545 am not going to continue arguing with this disscusion any more but To make you sure that I have OBDII and I monitor the eng. Temp. It reachs 96 c then fan operate to reduce temp (normal temp)…even when It have breech in the gasget I continued to ran the car and used it daily with OBDII monitoring for eng. Temp. but finally i decided to fix it because it might damage other parts due to high pressure in the water.

For the three head gasket leaks into the cooling system I’ve personally seen (Toyota, Ford, and Pontiac), the head gasket leak was the cause (not result) of the overheating problem. Wasn’t this the basic Subaru failure mode?