Ryan Lwin

Hey guys, my 95 civic radiator and coolant reservoir is acting different. I can't add any coolant to my reservoir or it just spew out after a few miles on the freeway. It doesn't spew out everything. It just does that enough. So, my car doesn't overheat. After stop driving for a few hours, all the coolant in reservoir would go back into radiator and left the reservoir empty. I thought radiator would have low coolant level but it doesn't. It has perfectly filled coolant.

It seems to be that my radiator isn't accepting anymore coolant than inside the radiator. Anymore amount added to reservoir just spew out. Is that normal? I have actually tested this for over a week by keeping an eye on my radiator. Coolant amount doesn't go lower in the radiator. Just no coolant inside the reservoir. What could be causing this?

Car doesn't overheat.
Fan comes on fine at right temperature.
Coolant rotates normal (when hot, expended coolant can be seen in reservoir and when cold, it goes back into the radiator)

Replaced the reservoir with new one and new cap.
Replaced radiator cap with AutoZone cap (not stock).
All hoses have been replaced
System is bled and no bubbles.

Former User

Top off the radiator and reservoir and then bleed the cooling system.

Ryan Lwin

Top off reservoir as in put to MAX line right? With cap on? I've actually tried that. It does that same thing. I've tired with coolant in reservoir at MIN too. Same thing but with less spill.

Would it affect the system if I open the reservoir after bleeding?

Former User

Did you do this:

Bleeding the cooling system may take 20-30 minutes.

1) Park the car on an inclined driveway with the front end higher than the rear.

2) Push/turn the dash heater lever/**** to MAX heat. Fan need not be on.

3) Follow the directions in the diagram below

Ryan Lwin

I did everything except I close the radiator cap after the fan came on the second time and topping off the coolant in radiator. Then I open the reservoir and fill to max. Then I turn the car off.

So I should turn the car off after fan comes on the second time and coolant is topped off without closing the cap? Should reservoir be filled before or after radiator is filled?

Former User

Your head gasket may be blown, allowing exhaust gas to enter the cooling system and blow coolant out of the reservoir.

Ryan Lwin

I don't see any oil or any black particles in the radiator. I checked with the radiator cap open while keeping the RPM at 2500. Also, there's no sign of water inside the engine. That I cannot really tell since I can only check the oil cap and dipstick. Don't see any water there. Definitely no smoke from exhaust. Any other signs I should check? I haven't done the compression test though. But I haven't notice any performance drop. RPM still gets to 7k easily.

grumblemarc

iTrader: (4)

YOu don't have to have coolant or oil contamination/mixing to have a blown headgasket.

Former User

Auto parts stores sell kits that test for exhaust gas in the coolant. You may want to buy a kit.

Blown head gaskets are complex to diagnose because they can manifest by any one of several different symptoms. It's unusual for all known symptoms associated with a blown head gasket to be evident.

Ryan Lwin

What test can tell me that my head gasket is blown?

I also tried revving the engine while radiator cap is open. Coolant level doesn't seem to be affected by that. Unless after getting hot. Then if I rev and release the throttle, coolant raises. I think that's normal since coolant expanded inside during rev. and rise up after release.

So, performance doesn't get affected in some cases? I thought engine would start losing power when head gasket is blown.

GRNcivEX

It does sound like your head gasket is blown. What your describing sounds exactly like what was happening in my old jeep.
When the coolants being forced out of the reservoir do you see any bubbles?

Ryan Lwin

I had bubbles but they go away after I open the reservoir and keep the RPM at 2500 till fan comes on. After that, no more bubbles. I checked after long drive too. Bubbles didn't come back. So, I'm not sure if the head gasket. I'll test the exhaust gas in reservoir.

Ryan Lwin

So, the problem was the radiator cap. Happened with 3 different caps. So, I finally looked up the Honda dealer site to see how much the caps are and it's only 10 bucks. Same price as Auto Zone. Bought it. Also bought Spill-Free Funnel. Bled it. Put it on. Nice and cool. Figures....

fragmare

Those aftermarket caps they sell at Autozone and O'Reilly are garbage. They're fine at first, but if you happen to open/close the cap a few times they start to leak. At least that's been my experience.

Ryan Lwin

Yup. They use cheap rubber that gets ruined after it heats up. You have to replace them everytime you open the cap. In my case, I kept trying to check the coolant level after a long drive and engine cool down. So, the cap is fine the first time I put it on and fail after I open it to check and put it back on. They did gave me money back since I tested it right in front of them.

I realized that this is the cap fault was because when I came home from school, which was like 30 minutes long drive on freeway, I opened the hood and put pressure on cap with my hand. Suddenly, I hear a gurgle noise. The coolant in reservoir was not going back in when thermostat is open. That's why it was building up in the reservoir.

Hope this help someone else.