Coolant return line blockage

[Ashleyc]

Good day all, im new here. Pleased to meet you all.
I have an issue i hope someone can give advice on.
I have a 2005 fiesta 1.6 duratec
I was having intermittent over heating issues after flushign the coolant. the temp needle would raise quite fast and usually drop just as fast. After a head gasket chemical test (passed) i changed the thermostat and temp sensor, and the problem is still there. So my mechanic discovered the coolant return from the head is blocked, as in air tight. He cleared some gunk our the little 90 degree metal bend pipe on the head, buts its still blocked in the head.
It makes sense that since changing the coolant i have had issues because i could possibly not fill the head with water if the air cannot escape.
We are battling to prod a wire wire down there, air compressor, just no luck and running out of ideas. I really done want to take the head off if i can help it.
Im now thinking putting the little rubber hose on, make it face upright and pour radiator flush down in the hopes it will soak a bit.
Anyone had this problem and any advice of a non invasive way of clearing the blockage?
Thank you all

 

[Mark 1971]

Good day all, im new here. Pleased to meet you all.
I have an issue i hope someone can give advice on.
I have a 2005 fiesta 1.6 duratec
I was having intermittent over heating issues after flushign the coolant. the temp needle would raise quite fast and usually drop just as fast. After a head gasket chemical test (passed) i changed the thermostat and temp sensor, and the problem is still there. So my mechanic discovered the coolant return from the head is blocked, as in air tight. He cleared some gunk our the little 90 degree metal bend pipe on the head, buts its still blocked in the head.
It makes sense that since changing the coolant i have had issues because i could possibly not fill the head with water if the air cannot escape.
We are battling to prod a wire wire down there, air compressor, just no luck and running out of ideas. I really done want to take the head off if i can help it.
Im now thinking putting the little rubber hose on, make it face upright and pour radiator flush down in the hopes it will soak a bit.
Anyone had this problem and any advice of a non invasive way of clearing the blockage?
Thank you all

Did you fix this issue with the blocked pipe at the head? I have same problem

 

[Handy Andy]

When the line gets blocked,this indicates some type of contamination in the coolant.

Meaning - either the cylinder head gasket leaked oil into the coolant side - or age of the fluid - the collected sediment has lodged or found ways - to rest and reside in areas of slower moving parts or areas of circulation - eventually collecting and causing a plug.

See This Thread...you might be able to locate the burp line on the Duratec motor you have - it's in a similar spot.
https://www.fordfiesta.org/threads/2011-fiesta-1-4i-heating-issues.7565/post-18720

The rear burp line - on a SIGMA motor is set up to provide a means for trapped gasses and provide a trickle flow method of letting the air pockets that form from hot spots when a hot engine is shut off - that can't get pushed out into the coolant recovery tank - a means to get there when the engine restarts and runs - the trapped air simply follows the line and burps out at the recovery tank.


You can try to remove the blockage, or free up the bubble valve that is located in the spot that burp line is at - using some stiff copper wire to help loosen the plug once you've been able to remove the hose from there.

Since you're finding issues with plugging, you can see about removing the plug just above it to investigate the problem - the oil that rises in the coolant from a broken or failed gasket in the head usually winds up caking and as it sits, forms a type of cement that only can be removed by physical means and tools. On top of the fact that a bubble valve rests here - designed to let the air escape, but leave the coolant behind - leaves the area in a position of having to be the spot where these problems usually crop up.

It is also an indication that due to this level of contamination, the cylinder head gasket should be replaced - you will have this same problem again later if you don't.