'97 Jetta coolant overflow

[kevin90]

So i have a 1997 Jetta GL and recently my coolant has been backing up into the overflow. It bust the original reservoir that was on there so i replaced it thinking it was just old and cracked, I put the new one on and let it warm up and the same thing happened. Then I assumed the thermostat might be bad and not opening so i replaced that and then again the same thing happened. I flushed the system and still no change.
I need some help here I'm stuck and have no idea what else could be causing this. Any suggestions?

[unknowable]

I have a few questions for you that should be able to help someone help you.

1.) is your engine temp gauge rising above 190 degrees?
2.) did you replace your reservoir cap?
3.) is your radiator fan coming on?
4.) what is the temperature where you are?
5.) did you fill your engine with coolant while the motor was running?
6.) are you using a proper mix of water/coolant?
7.) is your oil level adequate?

[kevin90]

Its going all the way up to 230.
Everything on the reservoir is new.
The fan works fine.
Its like 90 degrees outside.
I've filled both while running and while off.
I went and bought the coolant from the dealership so I'm pretty sure its right.
My oil is good, no white or bubbles either, and no white smoke

[unknowable]

Its going all the way up to 230.
Everything on the reservoir is new.
The fan works fine.
Its like 90 degrees outside.
I've filled both while running and while off.
I went and bought the coolant from the dealership so I'm pretty sure its right.
My oil is good, no white or bubbles either, and no white smoke

Okay so at Idle your car is overheating. You replaced the thermostat and reservoir (and cap i guess)

Now, the coolant system in these motors can be a PITA to fill without getting air in the system. A good way to test if the coolant is circulating properly is to turn your heater to the hottest setting and turn the fan on full. If you get hot air coming out of the vents, that means your coolant is circulating through the heater core.

If your heat does not get hot, or is only mildly warm, you have a flow issue and that would be due to a bad water pump or air in the system. (assuming the thermostat was installed correctly. not that I am doubting you)

The best method of filling your car with coolant is to leave the cap off of the reservoir, start the engine, and slowly fill it up. Squeeze your upper radiator hose frequently to assist with burping the lines.

Ive run into tons of issues with coolant systems just because there was air in the system and if your system has been completely drained it can be a pain to fill it up right. I hope this helps you.

[kevin90]

So i've rechecked and my fan is no longer coming on. Does this make any difference? And my heater does not get warm at all.

[MFBAB]

im having same issue. car over heats after idling for a while. Gets up to 230 degrees. Changed water pump, thermostat, fan switch. Fans dont come on at all unless I jump the switch and I also have no hot air at heater.(sometimes) Any Ideas.

[germancarnut51]

When you open the cooling system to replace parts and coolant is lost, air pockets are formed in the cooling system.

Once this happens, it take at least complete three heating and cooling cycles (with filling/topping the coolant ball) to eliminate most of the air from the cooling system. Until that is done, the engine will overflow the coolant ball, and spit coolant when you open the coolant ball to fill it when warm.

A heating and cooling cycle is composed waiting until the engine coolant does not register any heat on the temperature gauge, then taking off the top of the coolant bubble and filling the coolant ball. Starting the engine, and letting it run, message the upper radiator hose to help air escape, while watching for air bubbles escaping, then capping the coolant bubble when the air bubbles diminish, and the coolant expands and starts to overflow. At that time, you run the engine another five minutes, then shut off the engine, and allow it to cool down to cold, so you can repeat the complete cycle.