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Proper coolant bleed procedure?

Jabbit

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#21
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
I filled and purged, filled and purged, etc...and eventually it was fine. I don't believe a pump is needed. Mixing is easy, buy a 2+ gallon clear container on Amazon and you can get gallon distilled water at a pharmacy for sub-$2. Then it isn't really mixing so much as it is dump a gallon of coolant and gallon of water into the container, then pour.
 


kivnul

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#22
Many larger grocery stores also sell distilled water by the gallon. Usually about $1. I had no problem getting air out of my radiator just by using the bleed screw and keeping fluid in the overflow.
 


Erick_V

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#23
Many larger grocery stores also sell distilled water by the gallon. Usually about $1. I had no problem getting air out of my radiator just by using the bleed screw and keeping fluid in the overflow.
I run a 70/30 mix with water wetter and distilled water. Super cheap and only bought 1 jug of premix yellow coolant. I’m in Texas and in reality could get away with 100% distilled but I still choose to add some coolant
 


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#24
I didn't know these cars had a bleeder screw on the radiator. I bleed it by jacking the front up as air rises so trapped air will find its way up and out, fill reservoir to max, keep lid off, run the car with max heat to cycle the coolant into the heater core, run the car at 2500-3000rpm for a few minutes, you'll see the coolant drop, fill it up, and repeat.
 


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#25
Many larger grocery stores also sell distilled water by the gallon. Usually about $1. I had no problem getting air out of my radiator just by using the bleed screw and keeping fluid in the overflow.
Thank you. Do you mind explaining the bleeder screw process in a little more detail? Earlier in the thread someone suggested having the engine running with the heater turned to max while you have the bleeder screw open. That's still the consensus? I've also heard people rig some kind of container by the open bleed screw to catch excess fluid?

Also, I saw someone suggest leaving the overflow cap off during this process? Is that necessary? I'd think it could be dangerous due to the risk for coolant boiling over or dangerous to the engine?

Sorry for the dumb questions.
 


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SrsBsns

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#26
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
I have a '15 and I didn't use anything special and I've had no problems with overheating since installing my Mountune. Temps are consistently around 185.

You should be able to use the pre-mixed stuff, but I went with a lower ratio. I believe I used 60/40 or even higher, water to coolant. But I'm in San Diego and the coldest temps I'll ever see are in the 40's.
 


SrsBsns

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#27
Thank you. Do you mind explaining the bleeder screw process in a little more detail? Earlier in the thread someone suggested having the engine running with the heater turned to max while you have the bleeder screw open. That's still the consensus? I've also heard people rig some kind of container by the open bleed screw to catch excess fluid?

Also, I saw someone suggest leaving the overflow cap off during this process? Is that necessary? I'd think it could be dangerous due to the risk for coolant boiling over or dangerous to the engine?

Sorry for the dumb questions.
On the Mountune, there's a bleeder valve on the top of the radiator, facing the motor. I filled up the reservoir, then started the car. I left the cap off.

I let the car warm up. You can tell when the thermostat opens when you can feel the upper hose start to get warm. When the thermostat opened up, I turned the heat to max.

I used a waterbottle and some gloves and held the water bottle at an angle to allow the coolant to spill into the bottle. Just go slow with opening the valve. When you don't see bubbles coming out of the bleeder valve anymore, you should be good.
 


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#28
I used a waterbottle and some gloves and held the water bottle at an angle to allow the coolant to spill into the bottle. Just go slow with opening the valve. When you don't see bubbles coming out of the bleeder valve anymore, you should be good.
Thanks to all of you for the excellent guidance and your patience with me! On the step above, do you wait to open up the bleeder valve until the engine has fully warmed up or is it open the entire time like the reservoir cap?
 


kivnul

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#29
I put a tube on my bleeder to allow me to direct flow directly into a bottle. Personally, I had no need to run my cabin heater at all but it would not hurt to do so.

I wouldn't keep the bleeder open all the time otherwise your bottle would fill up quickly. I opened it up during initial fill to get the majority of air out and then closed it. Once the engine is warm (signified by the fan running at least once or you feel the lines and can tell that fluid is flowing by the output warming up) crack open the bleeder and let the fluid/air flow out. Once it is pure fluid for a few seconds, close it off and you are done.

Small bits of air left in the system will not hurt a thing and will work themselves out as you use the engine day after day.

Below is from the service manual. It uses a vacuum system to do the initial fill-up but is not really required. Note that it doesn't even use the bleeder valve to get rid of what little air is left:

1618267758990.png
 


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#30
I used some of the suggestions on this thread. My entire procedure:
  1. Put car on ramps
  2. Allow it to sit for about 1/2 hour to cool down.
  3. Open degas bottle cap. I bought some silicone grease from HD an put some on the 2 gaskets so it doesn't stick.
  4. Open the bleeder cap. This was a mistake and should have been done later - after the coolant has been drained from the lower hose. I sprayed coolant all over the intake manifold and got it all over the ground because the pan I placed underneath the car wasn't in the correct position to catch it all.
  5. After coolant stopped coming out the bleeder, place a 10" length of clear tubing on to the bleeder and other end into empty water bottle. The tube and bottle are kept lower than the bleeder.
  6. Used a pair of pliers to lock the constant tension clamp open on the lower radiator hose.
  7. Pull the hose off and let drain until it becomes a slow drip, maybe 1/2 hr.
  8. Put the hose back on and place the clamp back in the previous spot. This would be a lot easier if I'd marked the clamp and hose with some chalk. Next time, I'll do that or take a picture.
  9. Slowly start filling the degas bottle with coolant mixture. I picked up the discontinued carquest dexcool wannabe on clearance from Advanced Auto for about $4 and a gallon of distilled from Wallymart for my 50/50. You can go over the max fill line by a significant amount, since it'll slowly fill the entire system.
  10. Keep filling slightly pass the max fill until air and coolant starts coming out the bleeder. It took a very long time before any coolant comes out the bleeder. Maybe 1/2 hour. Once air stops coming out of bleeder, cap it off.
  11. Now to purge any remaining air. Fill to max fill and cap degas.
  12. Start car and wait for idle to stabilize. Rev to 3500 and keep there for 30 seconds. Shut off car for at least 1 min.
  13. Check degas level and add coolant until it reaches max fill.
  14. Start car and rev to 3500 for 30 secs. Let idle for 30 secs then shut off for at least 1 min.
  15. Repeat 13 and 14 until coolant level stabilizes and you no longer need to fill. I had to do it 2x total.
I drove for about 1.5 hours afterward and the coolant gauge stayed in the normal zone. I turned the heater on max while driving, was getting a stong blast of heat from the vents, and I was satisfied that I got most of the air out. In all, I think I got just over 1 gallon out. If I remember correctly, I think it was 6qt capacity. If that's the case, I got about 2/3 of the old stuff out. If you're anal about getting all of it, you may have to do 2 drain/fills.

DEss
 


FiestaSTdude

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#33
I used some of the suggestions on this thread. My entire procedure:
  1. Put car on ramps
  2. Allow it to sit for about 1/2 hour to cool down.
  3. Open degas bottle cap. I bought some silicone grease from HD an put some on the 2 gaskets so it doesn't stick.
  4. Open the bleeder cap. This was a mistake and should have been done later - after the coolant has been drained from the lower hose. I sprayed coolant all over the intake manifold and got it all over the ground because the pan I placed underneath the car wasn't in the correct position to catch it all.
  5. After coolant stopped coming out the bleeder, place a 10" length of clear tubing on to the bleeder and other end into empty water bottle. The tube and bottle are kept lower than the bleeder.
  6. Used a pair of pliers to lock the constant tension clamp open on the lower radiator hose.
  7. Pull the hose off and let drain until it becomes a slow drip, maybe 1/2 hr.
  8. Put the hose back on and place the clamp back in the previous spot. This would be a lot easier if I'd marked the clamp and hose with some chalk. Next time, I'll do that or take a picture.
  9. Slowly start filling the degas bottle with coolant mixture. I picked up the discontinued carquest dexcool wannabe on clearance from Advanced Auto for about $4 and a gallon of distilled from Wallymart for my 50/50. You can go over the max fill line by a significant amount, since it'll slowly fill the entire system.
  10. Keep filling slightly pass the max fill until air and coolant starts coming out the bleeder. It took a very long time before any coolant comes out the bleeder. Maybe 1/2 hour. Once air stops coming out of bleeder, cap it off.
  11. Now to purge any remaining air. Fill to max fill and cap degas.
  12. Start car and wait for idle to stabilize. Rev to 3500 and keep there for 30 seconds. Shut off car for at least 1 min.
  13. Check degas level and add coolant until it reaches max fill.
  14. Start car and rev to 3500 for 30 secs. Let idle for 30 secs then shut off for at least 1 min.
  15. Repeat 13 and 14 until coolant level stabilizes and you no longer need to fill. I had to do it 2x total.
I drove for about 1.5 hours afterward and the coolant gauge stayed in the normal zone. I turned the heater on max while driving, was getting a stong blast of heat from the vents, and I was satisfied that I got most of the air out. In all, I think I got just over 1 gallon out. If I remember correctly, I think it was 6qt capacity. If that's the case, I got about 2/3 of the old stuff out. If you're anal about getting all of it, you may have to do 2 drain/fills.

DEss
Thanks for the write up, just used this to refill my coolant after installing my mountune radiator
 


rallytaff

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#34
I couldn't put up with all that hassle, so I went to Mountune and had them install the radiator for me. Haven't had any problems.
 


FiestaSTdude

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#35
I couldn't put up with all that hassle, so I went to Mountune and had them install the radiator for me. Haven't had any problems.
I’m too broke for that lol
Is mountune a California based company? That’s pretty cool that you could go directly to them
 


Capri to ST

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#36
I’m too broke for that lol
Is mountune a California based company? That’s pretty cool that you could go directly to them
They are mainly based in England, but they have a branch in California. I remember when I got their tune that they would have installed it free if I had been able to go to them.
 


rallytaff

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#37
They are mainly based in England, but they have a branch in California. I remember when I got their tune that they would have installed it free if I had been able to go to them.
They're in Carson, about a 20min drive if the traffic allows.
 


Jabbit

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#38
Per the service manual - fill the expansion tank all the way up. Takes 10-15 mins as the coolant slowly drains down. Eventually it will stabilize at max. Start the car and hold revs at 3500 for 30 seconds. No HVAC. Shut off the car. Top off expansion tank again. Start car and let it get fully up to temp. Rev to 3500 and hold for 30 seconds. Shut off car for 1 min. Repeat the rev/off cycle 10 times. Let car completely cool. Check coolant level. Done.

What do I do? Fill coolant and let it settle, top of expansion tank. Pressurize system to 5-10psi a couple times with the kit below, filling between pressurizing. Start the car and let it warm up, keeping an eye on the expansion tank. Shutoff car, cool down, top off. Done.

Auto Cooling System Radiator Color Cap Pressure Tester Kit Pump Gauge Adapter HD https://a.co/d/06jWK4V
 


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#39
Is there a major downside to using PURIFIED bottled water vs Distilled bottled water? I made a rookie mistake when swapping to the Mountune Radiator last night and used bottled water in my garage. I didn't realize it until this morning that its PURIFIED (reverse Osmosis) drinking water and NOT distilled!!! I just read the bottle and it says its got added minerals - sodium bicarbonate & calcium chloride. I've only driven it around town about 25 miles or so to purge air from the system and am now worried that the added minerals in the water will mess up the cooling system... Should I Re-Flush my system immediately with DISTILLED water or do y'all think I will be okay with the bottled purified water I accidentally put in.... Thanks in advance everyone! I can't believe I overlooked this small but probably very important detail.... :oops::rolleyes:o_O:cautious:
 


Capri to ST

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#40
Is there a major downside to using PURIFIED bottled water vs Distilled bottled water? I made a rookie mistake when swapping to the Mountune Radiator last night and used bottled water in my garage. I didn't realize it until this morning that its PURIFIED (reverse Osmosis) drinking water and NOT distilled!!! I just read the bottle and it says its got added minerals - sodium bicarbonate & calcium chloride. I've only driven it around town about 25 miles or so to purge air from the system and am now worried that the added minerals in the water will mess up the cooling system... Should I Re-Flush my system immediately with DISTILLED water or do y'all think I will be okay with the bottled purified water I accidentally put in.... Thanks in advance everyone! I can't believe I overlooked this small but probably very important detail.... :oops::rolleyes:o_O:cautious:
I would be really surprised if it hurt anything in that short period of time, but maybe over time those extra minerals could cause a problem. If it was me I would redo it with the proper distilled water just for peace of mind. It's clearly bothering you (at least four emojis worth), and it would also bother me, so the sooner you change it you can just know that now it's right. I change my coolant every 3 years, and that would be a long time to drive around wondering if there was something wrong in there which was causing an issue.
If you're adding any kind of water, I'm assuming that you are also using concentrated coolant which requires dilution, not pre-mix, correct?
 


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