"Burping" the cooling system


New Member
May 13, 2005
Hey guys, Me again :nonono:

Anyways, I had an issue with the fan coming unplugged and the car overheating, which drained the coolant. I had the system flushed and refilled and the fan plugged back in, but I was told by a good friend that I needed to have the system "burped" due to the fact it is pressurized and will not cool properly if air bubbles are in the lines.. Can anyone give me some pointers on how to do this on a 96 cobra?

Thanks for all the help!!
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Official Ford Documentation
Cooling System Draining, Filling and Bleeding


WARNING: Never remove the pressure relief cap/radiator cap under any conditions while the engine is operating. Failure to follow these instructions could result in damage to the cooling system or engine and/or personal injury. To avoid having scalding hot coolant or steam blow out of the cooling system, use extreme care when removing the pressure relief cap from a hot degas bottle or the radiator cap from the radiator. Wait until the engine has cooled, then wrap a thick cloth around the pressure relief cap and turn it slowly one turn (counterclockwise) or with a thick cloth around the radiator cap turn the radiator cap (counterclockwise) slowly to the first pressure stop. Step back while the pressure is released from the cooling system. When certain all the pressure has been released, remove the pressure relief cap/radiator cap (still with a cloth).

CAUTION: The coolant must be recovered in a suitable, clean container for reuse. If the coolant is contaminated it must be recycled or disposed of correctly.

NOTE: About 80% of coolant capacity can be recovered with the engine in the vehicle. Dirty, rusty or contaminated coolant should be drained and filled with new coolant.

Release the pressure in the cooling system by slowly turning the pressure relief cap one half turn counterclockwise or the radiator cap counterclockwise to the first stop. When the pressure is released, remove the pressure relief cap/radiator cap.

Place a suitable container below the radiator draincock (8115). If equipped disconnect the coolant return hose at the fluid cooler. Drain the engine coolant.

Close the radiator draincock.


All engines

Place the heater temperature selector in the maximum heat position.

2. CAUTION: On 3.8L engines, the vent plug must be removed before radiator fill or the engine may not fill completely.

NOTE: It is important to maintain engine coolant concentrate between 40 percent or -24°C (-11°F) and 60 percent or -52°C (-62°F).

Fill the engine cooling system with 50/50 mixture of water and engine coolant E2FZ-19549-AA (in Oregon F5FZ-19549-CC, in Canada CXC-10) meeting Ford Specification ESE-M97B44-A.

3.8L engines

After filling the engine cooling system, add coolant to the vent until full. Install the vent plug.

All engines

4. Leave the pressure relief cap off and run the engine until it reaches normal operating temperature.

5. Stop the engine and add the correct engine coolant mixture to the degas bottle/coolant expansion tank until the coolant level is between the COOLANT FILL LEVEL marks.

6. Turn the engine off and allow the cooling system to cool. Check the level in the degas bottle/coolant expansion tank, and add a 50/50 mix as needed.


1. Select the maximum heater temperature and blower motor speed settings. Position the control to discharge air at A/C vents in instrument panel (04320).

2. Start the engine and allow to idle. While engine is idling, feel for hot air at A/C vents.

3. CAUTION: If the air discharge remains cool and the engine coolant temperature gauge does not move, the engine coolant level is low and must be filled. Stop the engine, allow the engine to cool and fill cooling system.

Start the engine and allow it to idle until normal operating temperature is reached. Hot air should discharge from A/C vents. The engine coolant temperature gauge should maintain a stabilized reading in the middle of the NORMAL range. The upper radiator hose (8260) should feel hot to the touch.

4. Shut the engine off and allow the engine to cool.

5. Check the engine for coolant leaks.

6. Check the engine coolant level in the degas bottle/coolant expansion tank and fill as necessary.