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Proper coolant bleed procedure?

PunkST

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#1
So when i had to do the starter earlier in 2020 i had to lose some coolant to get enough room for replacing it. Since then, after filling it and running it with the heater on full blast. My car whistles like a teapot when the heat is on. I assume there is still air trapped in the core.

Anybody know the reccomended procedure to stop the teapot whistling?.
 


TyphoonFiST

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#2
A Vacuum bleed may be required* IMO... Have you tried Pulling the bleeder in the middle of the top of the radiator while using a clear hose in the bleeder port and clear bottle to catch any coolant and watch for air bubbles?
 


OP
PunkST

PunkST

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Thread Starter #3
A Vacuum bleed may be required* IMO... Have you tried Pulling the bleeder in the middle of the top of the radiator while using a clear hose in the bleeder port and clear bottle to catch any coolant and watch for air bubbles?
No. I may not have the center bleeder as the rad is an aftermarket piece. ( factory style koyorad, didnt have a say in it as it was done by the "repair" shop)

I can look for the bleeder though. I may need to pressure bleed it to get the air out of the heater core like you said.
 


TyphoonFiST

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#4
ill bet the bleeder is there right in the top middle. Its just a little plug. Be careful as they break easily* FYI..... My OEM one was broken during removal and another one was bought from ferd for like $5 to go into my Mountune radiator.
 


OP
PunkST

PunkST

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Thread Starter #5
Ok. Ill look this week. Id rather not risk breaking it if they are flimsy.
 


OP
PunkST

PunkST

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Thread Starter #7
I should flush to the yellow coolant anyhow.. Lol
 


OP
PunkST

PunkST

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Thread Starter #9
Fair point. I still have some jugs of orange.
 


SrsBsns

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#10
Yeah, the bleeder valve should be in the middle, facing the front/pass side. It was there when I did my Mountune. Get the car up to temp, blast the heat and then open the bleeder valve until you don't have any more air coming out. I didn't find fishing hose that fit over the bleeder but I was able to get a water bottle almost all the way on there to make sure I didn't make a huge mess. Just wear gloves when holding the water bottle.
I'd stick with the orange stuff too if you can.
 


OP
PunkST

PunkST

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Thread Starter #12
Ok i found the nipple. I wonder if i should jack up the car. The air is trapped in the heater core. After all. Or would that not be reccomended.
 


SrsBsns

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#13
I don't think it's necessary to jack it up. I had mine flat on the ground when I bled the system and (knock on wood) haven't had any problems since.

To get the air out of the heater core, just turn the heat on inside the car to max and let it blow, once the car has been warmed up. You can wait until you feel warm/hot coolant running through the upper rad hose. You can also massage the hoses to help encourage any air out of the system.
 


kivnul

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#15
I am not sure I would bleed a fully heated up system: Would be both pressurized and scalding. I would first bleed it when cold, and (with the heater running at max) check the bleed every minute or two with it idling. Someone please correct me if I'm wrong here.
 


OP
PunkST

PunkST

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Thread Starter #16
Its gotta get up to temp to have the thermostat open up. As far as i know the rad really doesnt see much pressure till that happens. And even less if the overflow cap is off. Yes it will be hot AF, so the best plan is wearing gloves and not sticking your face down there.
 


OP
PunkST

PunkST

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Thread Starter #17
When I replaced the old orange coolant with the new yellow coolant, I learned that, while filling up the coolant reservoir, the bleeder screw on the top of the radiator has to be off until the new coolant starts coming out. This method eliminates so much potential air in the system.
That must be the step i didnt know about. I hope i can get the system purged now.
 


SrsBsns

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#18
Its gotta get up to temp to have the thermostat open up. As far as i know the rad really doesnt see much pressure till that happens. And even less if the overflow cap is off. Yes it will be hot AF, so the best plan is wearing gloves and not sticking your face down there.
Yeah, I was going to say this. Until the car reaches temp, the thermostat stays closed and you won't get coolant flowing throughout the system. Wear gloves. Pay attention and be safe.
 


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#19
I'm thinking of upgrading my radiator to the mountune one on my 2017. I keep seeing conflicting information about the need for a vacuum fill pump to purge air? Is it or is it not needed? Or, is filling the reservoir while the bleeder cap is off (until it starts spilling coolant) sufficient?

Also, can i just buy premixed Ford compatible coolant and call it a day or do I really need to mix this myself?

Thanks,
Steve
 


Erick_V

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#20
No fancy tools needed. I’ve changed the fluids twice, used all the tips above and bled the system with the car off the jacks and on level ground. Ford sells premixed 50/50. Ask for the yellow coolant, I flushed my system a couple days ago and it was $15 for the gallon jug
 




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