Air in my radiator.

svtcobrar2004

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Hello, ran into an issue where my cobra has air in the inter cooler lines or somewhere. I did the steps of removing the crossover plug and filled it there, squeezed the line and it was moving the fluid on the crossover. Heat was on and the car is on a slight incline. The fluid in the degas tank rises to the top of the tank when I let the car run though. I can't get it to burp. Thanks!
 

P49Y-CY

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is it overheating? even if it is burped properly, the level in the reservoir rises when it approaches operating temperature. (edit: i mean with the cap closed)
 

DSG2003Mach1

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The intercooler is a separate system

you will never get the crossover 100% filled to the opening unless you using a vacuum system on the expansion tank. If the coolant level is in the marked range of the tank when cold and not overflowing when warm I don’t think you have a problem unless you’re leaving out info
 

svtcobrar2004

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When cold, the fluid sits below the marked line. When the car gets fully warmed up, it will not pump the fluid in the degas bottle and the car will start to over heat. I'll let it sit for a while (20 mins) and the fluid will go down, letting some of the pressure out with the degas cap and the car will drive just fine, no overheating. It's pumping fluid and the temps are in normal range. I go to start my car up again a few days later and I run into the same issue.
 

DSG2003Mach1

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You do not see circulation in the degas bottle to be clear

what are you using to judge that it’s over heating? Are you actually hearing the degas bottle vent?
 

svtcobrar2004

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Now that you mention it, I don't see circulation.

Yes, I am hearing the degas bottle vent from the cap.

Maybe it's my water pump?
 

olympic

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DSG2003Mach1

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If you aren’t seeing the temp gauge move (I would suggest booking up a scan tool) I’d tend to think you might have a bad cap or res
 

svtcobrar2004

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The digital gauge I have appears to be working. It was reading over 200+ not too long ago and saw that the degas bottle wasn't pumping, I let it sit for a while and it appears to be working and the temps are normal (170ish)
 

svtcobrar2004

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Burping the cooling system is done with a funnel wrapped with teflon tape and screwed into the crossover.

Ford 4.6L DOHC Coolant Refill & Burp Procedure by Reische Performance Products

Other possibilities are the thermostat is sticking closed or you have a blown head gasket and air is being forced into the cooling system. It's very unlikey that the water pump is not working.

I tried that but I cut the funnel so it fits into the crossover just snug. Thank you for the write up it's a lot better written.

How much coolant should I keep adding to the crossover while I am trying to purge the air? I filled the crossover (once so far) to about a 1/4 in the funnel and squeezed the 2 lines and the coolant did recede. Should I keep adding fluid until I can't? when should I know I've added enough antifreeze? Thanks
 

hotcobra03

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Burping this car is easy.

From reading this thread I’m confused

You mention intercooler

2 different systems here

Supercharger degas tank you will see movement

Radiator tank you will not see movement

Here is my suggestion.

Drain the system.

Check tstat for proper tstat and test it in boiling water

When you reinstall. The system holds about 4 gallons.

A gallon or so is left in motor
Now pour 3 gallons into car
Fill radiator till you can’t anymore

Than pull cross over plug

Full here till it flows out of radiator
Install cap. Than fill cross over till full

Run car till low speed fan kicks.

Shut off and repeat

Also. Tstat some of use have drilled tiny holes to help air pockets from forming.


At this time cars are old.

Radiator flow is an issue and will cause car to overheat

A cracked head is common will cause this issue also.
 

01yellercobra

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200 isn't overheating in these cars. I think the low speed fan doesn't come on until 210 or something like that. If you're not boiling over you're not overheating. If you're hearing a hissing sound replace the radiator cap as mentioned.
 

wckdvnm

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As said above me 200 isn’t overheating; factory low speed fan comes on at 212 High at 220ish.


Sent from my iPhone using svtperformance.com
 

Eman45

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Had issue with my 03. Coolant pours out the overflow cap when hitting boost hard. Other then that cars drives fine I made sure I bled it out and didn’t overfillnit. And drives fine under regular driving conditions. Won’t over heat or anything. Soon as you get on it tho the coolant blows right over. Think the heads lifting under pressure when in high boost causing a pretty nasty head gasket leak
 

svtcobrar2004

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Thanks for the reply guys. But when I fill from the crossover, how much antifreeze should be enough? When will I know it's enough? Thanks!
 

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