Bubbles in radiator

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escortwgn

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There's a lot of bubbles in coolant. Had it tested to see if head gasket had blown, according to the test it is not blown. No signs of leaks where it could be grabbing air. Attempted to replace all gaskets including head, but one bolt was stubborn and I was unable to do the heads, but every other gasket was replaced and torqued down properly. The lower intake was not very well tightened when I took it off and believed that to be the problem. But obviously not, because it's still doing it. I have the coolant sys open to the atmosphere via the over flow to allow the air to escape without blowing the rad cap off. It does not over heat, there is not fluid contamination, and no leaks. I really don't know what else it could be. Hopefully this is not the first time anyone has heard of this.

Thanks in advance!!

 

miesk5

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Yo Justin,

Try Burping the coolant system; this is by Ford;

Beware of Hot Engine, fan blades, belts, pulleys.

1. Fill the radiator with a 50/50 mixture of the specified engine coolant concentrate and water. Allow several minutes for trapped air to escape (bubble out) and for engine coolant to flow through the radiator.

2. Replace the radiator cap to its fully installed position, then back off to the first stop. This will prevent high pressure from building up in the cooling system during this part of the fill procedure.

3. Start and idle the engine until the thermostat opens and the radiator upper hose becomes warm.

4. Shut off the engine and allow the engine to cool. Cover the radiator cap with a thick cloth and cautiously remove it. Step back while the pressure releases.

5. Finally, check the radiator and add more engine coolant if needed, following the procedures noted above. Reinstall the radiator cap securely, when finished.

6. If more engine coolant is necessary, fill the overflow reservoir to the appropriate level marked on the bottle..."

 
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does the system pressurize instantly when starting cold? system capped like normal, start the engine. after 1 minute, is the system already pressurized to the degree that hoses are firm/opening cap relieves lots of air? if so, i'd definitely say a head gasket is leaking combustion gasses into the cooling jacket. the system should never pressurize before the engine warms up, if that makes sense. the fact that the heads were loosened and re-tightened with original gaskets is not good.

 
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escortwgn

escortwgn

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I've burped the sys many times since the last post. The lower intake manifold rear gasket began gushing coolant out of the blue. So I replaced the gaskets today and the water pump decided to start leaking. Long story short, pump is bad. Replacing it tomorrow in hopes that was the problem.

 
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escortwgn

escortwgn

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does the system pressurize instantly when starting cold? system capped like normal, start the engine. after 1 minute, is the system already pressurized to the degree that hoses are firm/opening cap relieves lots of air? if so, i'd definitely say a head gasket is leaking combustion gasses into the cooling jacket. the system should never pressurize before the engine warms up, if that makes sense. the fact that the heads were loosened and re-tightened with original gaskets is not good.
 
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escortwgn

escortwgn

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Problem solved. It was a combo of two issues. First the water pump. Second, since I was using water instead of coolant to trace out the problem vrs spending the money on coolant, the water was actually boiling today. Didn't pressurize today but I burped it and all the air pockets came out and did not return!!!!

 

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