"Burp" of Coolant on This Hot Day
 

The '03 I recently purchased released coolant from the area of the overflow bottle pressure cap today.

There was no indication of an overheating condition while driving the car. I had been driving at reduced highway speeds in traffic in this hot weather. The AC was not running. When I parked and turned off the car, that's when the coolant flowed free. The level in the bottle was at the Low mark after that.

I drove the car back to where I store it, and it indicated no overheating condition on the gauge. I had driven the car previously around town and had no issues, with and without the AC running.

I am wondering if there was air leftover in the system after the previous owner changed the coolant when he replaced a leaking T-connector. Any thoughts or previous experiences welcome.

Re: "Burp" of Coolant on This Hot Day
 

Yep, sounds like you had an air bubble in the system. There is a plug in the coolant crossover on top of the engine that is supposed to be taken out to "burp" the system when changing the coolant. Sounds like this may not have been done.

Re: "Burp" of Coolant on This Hot Day
 

Thanks for the info. It's been awhile since I've looked at these engines, and I had forgotten about the plug. Oddly enough, when I had the coolant changed at a dealership on my first Mach 1 back a number of years ago, I had the same thing happen. Perhaps that wasn't done then either.

Re: "Burp" of Coolant on This Hot Day
 

A couple years ago, I had forgot that I had removed the fuse for the cooling fan. When you upload tuner files to the ECU, the stupid cooling fan runs through the whole process and I didn't like that drawing from my battery. Anyway, back to the story...so the following day, I participated in Independence Day parade. It was fun until steam started flowing out of my engine bay, along with about a liter of coolant from my fill cap. I didn't know this at the time, but the plastic cap will open when a certain pressure is reached. Once I shutdown the engine, it stopped flowing out and was okay. Apparently once this has happened, it is suggested that you replace the cap. I bought a new cap from my local Ford dealership and everything was fine...after I put the cooling fan fuse back in LOL. The cap was around $15, if I remember right. Maybe your cap has opened before with the previous owner and needs to be replaced?

Re: "Burp" of Coolant on This Hot Day
 

Thanks for the information. I think he obviously had the cap off when he had the coolant replaced. He's been out of town so I haven't had a chance to talk with him. I will check on the cap situation for sure.

I recall having this happen on my original 2003 after a coolant flush at a dealership. One would presume they would have gotten the air out of the system, but apparently it didn't happen. At that time, the coolant was topped off and that was it.

Re: "Burp" of Coolant on This Hot Day
 

The cap on the overflow bottle was not Ford OEM but aftermarket. It just didn't hold the pressure, resulting in the burp. When I unscrewed it, the cap came off very easily. A factory one has replaced it. So far, so good (knock on wood).

Re: "Burp" of Coolant on This Hot Day
 

glad it was an easy fix, I was going to suggest a bad cap and or bottle as well

Re: "Burp" of Coolant on This Hot Day
 

Nice!!