Air stuck in heater core

[BrianX128]

I made the mistake of getting some air in the system taking the radiator cap off a wee bit hot the other night, now when I go down hill for a bit I have air traveling to my heater core and sounding like someone is running water when I accelerate for 3 seconds until the air moves on. I've tried parking on a steep hill and getting the air to the top as best as I can but I can't quite get it all out.

I've made sure I don't have any bubbling in the radiator or anything to cause anymore air to get into the system I'm just unsure how to get this air out. It isn't much but it's driving me nuts thinking I have it all and going down my driveway and hearing the gurgle in the glove box when I accelerate for a few seconds.

 

[IDIBRONCO]

Maybe you need to turn on your heater and let the water pump push the air through and back into the engine?

 

[IDIBRONCO]

Maybe you need to turn on your heater and let the water pump push the air through and back into the engine?

Hopefully you know that I meant to do this with the engine running at operating temperature.

 

[MtnHaul]

Maybe you need to turn on your heater and let the water pump push the air through and back into the engine?

Correct me if I'm wrong here, but isn't coolant constantly flowing through the heater core?

Also, my truck has made that gurgling noise for a couple years but only when I start the truck for the first time of the day.

 

[franklin2]

To get the air out, all you have to do is get it up to temp with the radiator cap off. When the thermostat opens, the air will naturally work it's way out the top of the radiator with the cap off. Then make sure your overflow has some fluid in it, and while it's still hot put the radiator cap back on. When it cools, it will draw in coolant from the overflow tank.

Only problem with this, it's sometimes difficult to get these engines up to temp. In the summer it's not too bad, but in the winter it's almost impossible to get it to warm up enough just sitting idling in the driveway.

 

[Noiseydiesel]

Yeah, It was working good until you removed the radiator cap and disturbed the seal, right?
Simply put since the seal was disturbed you need to get the seal re-established on the cap.
That rad cap has two seals on it if you look at it. The bottom seal caps off the radiator. The top seal caps off the over flow jug. The bottom seal on your cap is allowing the air to enter back into the engine.
Get yourself another brand new radiator cap, drive it a day or two and you problem should fix itself.

 

[Clb]

Which truck?
I recall the obs has the pipes up top on the core, last searches I did claimed to burp the system out the core after the petcock statt,waterpump shindig...

 

[BrianX128]

Lol I thought I had it today, once I let it cool off on level ground it still did it yet it will stop once I drive it for a couple minutes. The sound almost sounds like the inlet of the heater core is clogged and it's getting fired into the core like a narrower jet then a full flow.

 

[Noiseydiesel]

Radiator cap replaced yet?
Gotta run, looking for info on my . . . "project". Yeah. That's whut it are.

 

[Cubey]

Correct me if I'm wrong here, but isn't coolant constantly flowing through the heater core?

My E350 IDI has a vacuum operated valve on one of the heater hose lines.

 

[BrianX128]

I believe I got it figured out now, I ended up pulling the core to make sure it was good and flushed it out, then filled it with distilled water and put it back in and filled the two hoses up with antifreeze while holding them up in the air, haven't heard the noise since. Stupid overflow was down halfway between cold fill and the bottom this morning once it had cooled down again for the second time, hoping it's just burping out any of the last air pockets that were in the system. No signs of anything wrong as far as coolant in oil or bubbles in the radiator, smoke or smell from exhaust, etc. I put a new cap on the radiator also.

 

[Cubey]

Stupid overflow was down halfway between cold fill and the bottom this morning once it had cooled down again for the second time, hoping it's just burping out any of the last air pockets that were in the system.

Yep. It will suck in coolant to refill itself when it cools down until there is no air left at the top of the radiator.

 

[Story big blue]

Correct me if I'm wrong here, but isn't coolant constantly flowing through the heater core?

Also, my truck has made that gurgling noise for a couple years but only when I start the truck for the first time of the day.

Yep. It will suck in coolant to refill itself when it cools down until there is no air left at the top of the radiator

Yep. It will suck in coolant to refill itself when it cools down until there is no air left at the top of the radiator.

 

[Story big blue]

On bottom left side of rad there’s a 1”hose that bleeds air out heater core of system it might be plugged