AIRLOCK causing coolant to shoot out of Radiator Cap?

[searcherrr]

Anyone here ever experienced airlock causing coolant to come out of the radiator cap and after a successful air burping of it all everything was fine?

Contemplating replacing the 3rd party radiator with OEM. Fluid won't go back n forth to overflow reservoir as its supposed to. Already checked for blockages etc..

[olopezm]

It happened to us once, a long time ago.

The coolant would get spilled all over the place when after driving for some time; you could even listen to it burping and bubbling in the reservoir. It even lead to overheating and we had to rebuild the engine for a second time. MAKE SURE the water pump is OK I don't know in your model, but in mine the impeller was all rotted and wouldn't operate properly.

What we did to get rid of it was to bring the engine to normal operating temperature, turn the heater to the MAX setting and rev the engine to 2k RPM's for 30 seconds, ask an assistant to do it while you take a look at the reservoir. DON'T let it run out of coolant, top it as necessary. Let it idle for 30 seconds and repeat until the coolant level is steady in the reservoir.

Oscar.

[searcherrr]

Well, this is exactly what happened. AIR or VAPOR lock. I figured it out after calming down and thinking logically about it. The service cap (made of rubber) that is perpendicular from the radiator cap constantly would rot out and crack and allow air to get sucked into the radiator... very slowly... ever so slowly over time and eventually when the air adds up to enough it'll cause an overheat problem. Lucky for me all of my cooling components are new, including the water pump, but I don't doubt that this event has taken some life off of it all since it got up to the "H" momentarily while slowing down on the interstate.

What you will notice when you have this problem (while on the road) is that the a/c will stop working, temp gauge will go way up above the usual normal range and the big one that I found interesting.... the heater won't work. Normally in an overheating situation (say a water pump failure) you'd notice it going hot, but turning on the heater would allow it to cool faster. In this case with air inside instead of coolant, the heater didn't blow any hot air, I guess because there was not enough or "no" hot coolant flowing through the heater core to blow hot air.

I put my Windstar on almost about a 40 degree angle with parking brake on for about an hour and slowly filled it up with almost 2 gallons of 50/50. It spat back at me a few times (have towels on hand to catch it out the radiator spout) when it was full, but then it would go down again allowing me to pour more in. Even after a full hour (and mind you I have sealed my service spout with jb water weld; leaving the only direction out for the coolant to be through the radiator cap into the reservoir jug or out from under the rad cap itself)... so... even after a full hour of burping the coolant I could still see air bubbles rising in the coolant reservoir. I plan to burp it again sometime soon, but for now its been holding steady between the A and M on the temp gauge and I've driven it 660 miles roundtrip somewhere and had no problems with overheating... all because of a simple process known as "burping".

lol - OMG. At least now I will have an extra OEM radiator on hand (still in shipping on its way).

[12Ounce]

Originally Posted by searcherrr

................ Already checked for blockages etc.......

What does this mean? How did you accomplish? What exactly was the outcome?

If you think you have a coolant circulation issue, it may be best to remove the thermostat until you get the circulation issue resolved.

From earlier posts (you start a number of posts, don't you?... can be a bit confusing.), you spent some efforts and time trying to use a leaking radiator. Could it be this led to the engine being overheated to the extent that the head gasket was blown? If so, you may never keep coolant in the system. (I hate to be the old "ogre" ... but bad things sometimes happen.) It may be time to take a "compressed air blow down test" on each cylinder while turning the crank over slowly by hand ... through TDC on the compression stroke. If the head gasket is blown, there will be crank-positions that allow a lot of air to be blown out through the compression chamber ... THIS ONLY HAS MEANING IF THE VALVES ARE CLOSED ON THE CYL BEING TESTED.