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92 Sc400 Cooling Issue 2023

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Old Jul 20, 2023 | 04:44 PM
  #16  
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Any chance your heater core is gunked up??

I started with a cold car, both points open.
I filled the expansion tank first as to keep as much coolant in the engine as possible. Since the engine's top part is the highest I filled this last.
I used the expansion tank. My apoligies I've been dealing with cooling system from 3 different perspecrives this last year.

LEXLS dot com has a good tutorial about this but it's an LS. Same difference I followed the bleeding process from here Using the expansion tank with a funnel like you did, but I had mine filled half way up. Since it will gargle up coolant quick, and alllows you to see the bubbles come up.
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Old Jul 20, 2023 | 05:14 PM
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Originally Posted by Tallyhoe
Any chance your heater core is gunked up??

I started with a cold car, both points open.
I filled the expansion tank first as to keep as much coolant in the engine as possible. Since the engine's top part is the highest I filled this last.
I used the expansion tank. My apoligies I've been dealing with cooling system from 3 different perspecrives this last year.

LEXLS dot com has a good tutorial about this but it's an LS. Same difference I followed the bleeding process from here Using the expansion tank with a funnel like you did, but I had mine filled half way up. Since it will gargle up coolant quick, and alllows you to see the bubbles come up.
how would I check if the heater core is gunked up? each time I do the process my heat gets pretty hot gradually mostly when I rev the car up a bit. anyway I could get in contact with you? im out here rn and still a bit confused.
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Old Jul 21, 2023 | 06:38 AM
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Originally Posted by vvvs
how would I check if the heater core is gunked up? each time I do the process my heat gets pretty hot gradually mostly when I rev the car up a bit. anyway I could get in contact with you? im out here rn and still a bit confused.
From the white stuff coming out through your expansion tank. There is a way to clear it out, you will need to remove the heater inlet and outlet. Here is a youtube vid on it with Eric the car guy... There are other vids like ChrisFix, but some people don't like that guy, so I'll go with this vid. LOL...
Inlet you will stick a hose in and maybe a hose on the outlet to control outflow into a bucket, instead of your engine bay or the floor. it will evaporate anyway, but no one wants stains on the floor, or hazardous waste on the floor. Maybe whatever is in your radiator may be gunkin up your water pump, or in your thermostat. Unless your thermostat is broken out of the box and causing you issues from the jump.
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Old Jul 22, 2023 | 04:32 PM
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Originally Posted by Tallyhoe
From the white stuff coming out through your expansion tank. There is a way to clear it out, you will need to remove the heater inlet and outlet. Here is a youtube vid on it with Eric the car guy... There are other vids like ChrisFix, but some people don't like that guy, so I'll go with this vid. LOL... https://youtu.be/dcL_0TWeZJY
Inlet you will stick a hose in and maybe a hose on the outlet to control outflow into a bucket, instead of your engine bay or the floor. it will evaporate anyway, but no one wants stains on the floor, or hazardous waste on the floor. Maybe whatever is in your radiator may be gunkin up your water pump, or in your thermostat. Unless your thermostat is broken out of the box and causing you issues from the jump.
I finally *****ing did it, I started the car with the cap off and the filler hole open with a funnel in it, and I filled the filler hole only when it got low and hella bubbles were coming out of the tank. thank you all, I wish I could buy you all lunch😭 because i’m pretty sure one of you guys gave me those exact instructions. “car didn’t overheat quickly at all, I took my eyes off the car for a minute and forgot to fill the hole and temp started creeping” at this point I know not much air is in this system anymore so im waiting for it to cool down and finish up.
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Old Jul 22, 2023 | 04:48 PM
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Originally Posted by vvvs
I finally *****ing did it, I started the car with the cap off and the filler hole open with a funnel in it, and I filled the filler hole only when it got low and hella bubbles were coming out of the tank. thank you all, I wish I could buy you all lunch😭 because i’m pretty sure one of you guys gave me those exact instructions. “car didn’t overheat quickly at all, I took my eyes off the car for a minute and forgot to fill the hole and temp started creeping” at this point I know not much air is in this system anymore so im waiting for it to cool down and finish up.
Forward progress is always fulfilling. Glad you're getting it sorted out.
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Old Jul 25, 2023 | 10:21 AM
  #21  
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Awesome news - way to stick with it and make it happen! Now go enjoy that bad boy.
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Old Jul 26, 2023 | 08:30 AM
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Originally Posted by RudysSC
Awesome news - way to stick with it and make it happen! Now go enjoy that bad boy.
lol got all the air out today, temp still creeps up at idle so i give up now, thanks for all the help
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Old Jul 27, 2023 | 05:04 PM
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Default leaking iacv

this is gonna be my last time taking everything apart. I noticed my iacv was leaking drops of coolant after I cleaned it. i’m sure I have to replace the old hoses, anyone know how to source them? and would the leaking coolant de-pressurize the system causing overheating?
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Old Jul 28, 2023 | 09:33 AM
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It's possible if you're leaking that air is making it's way in... If those parts aren't available new anymore you may have to take them to an auto parts store and have them let you look through their hose selection. Find some hoses with similar bends and trim to suit. I believe you can also bypass the coolant to that all together, but double check on that first just in case.
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Old Aug 24, 2023 | 04:53 PM
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Originally Posted by RudysSC
It's possible if you're leaking that air is making it's way in... If those parts aren't available new anymore you may have to take them to an auto parts store and have them let you look through their hose selection. Find some hoses with similar bends and trim to suit. I believe you can also bypass the coolant to that all together, but double check on that first just in case.
went back to the oem temp sending unit, and I replaced the leaking hose now all works well, much appreciated 🙏🏽
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