heater core?

2000 CHEVROLET BLAZER
110,000 MILES • 4 CYL • 2WD • AUTOMATIC
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SIS SWINDALL
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how do yo remove the dash to replace heater core?
Sep 7, 2009 at 5:27 PM
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BLUELIGHTNIN6
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https://images.2carpros.com/forum/automotive_pictures/261618_Noname_945.jpg

Sep 7, 2009 at 8:40 PM
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LJK730
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My husband needs to replace the heater core in his 2000 2DR, 4WD blazer with AC, which presently has about 80,000 miles. However, and understandably, he is a little concerned as to how involved this will be because he will need to remove the steering column and dash...any suggestions/recommendations? Please! And thanks!
Aug 19, 2020 at 8:15 PM (Merged)
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LOSONE
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It is about an 8 hour rough job for an experienced mechanic. For a novice about 3 days
Aug 19, 2020 at 8:15 PM (Merged)
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QUIETSOUTH
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How much is it going to cost to get the heater core replaced? Or how can I replace it my self?
Aug 19, 2020 at 8:15 PM (Merged)
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SWILLIAMS
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300-600 dollars depending on the shop. You can DIY if you want. You basically need to pull the dash out and then R&R the core. I would say that you want a copy of the service manual to determine if you wish to do it. Mitchell online works pretty well and it's worth the money.
Aug 19, 2020 at 8:15 PM (Merged)
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LOISENGLENY
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Heater problem
2000 Chevy Blazer 6 cyl Two Wheel Drive Automatic

Hi! My heater core went and I am having someone replace it. He has had my vehicle for two days now. I called today and he stated that he can't get the heater box out of the way to get to the heater core. He says he only found two bolts...where are the others? Please help...my truck has been broken down for weeks...I need my ride! :(
Aug 19, 2020 at 8:15 PM (Merged)
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BLUELIGHTNIN6
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Here's a tip to give your repair person.

" I started by taking the hoses aloose. Then move the blower resister. Look down in there---unscrew a bolt going the firewall into the blower housing. There is a stud coming through the firewall in the middle. Takes 7/16 socket--take care of that one. Now go to the inside and take the whole dash and put it in the backseat. Scews at the top. A 10mm headed bolt on each side. Drop the column down. Need to do some unplugging. Remove glovebox and you got a big electrical connector-use 7mm socket. A vac. connector. Get some slack going for the ant. cable. IMPORTANT-- Take aloose one connector at bcm(plastic box in middle). The one at the top going to dash.I almost pulled it by the roots. After pulling the dash back a little you will see a connector on driver's side with big wires---get it. And get the ant. cable out the back of radio. None of this bad to do. The housing has a 10mm headed bolt at bottom and two screws coming in backwards through the firewall. Undo the bolt. I used a hammer and big screwwdriver on the other two underthere. Yank back-do the core"

See if that helps them out..
Aug 19, 2020 at 8:15 PM (Merged)
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PERCYK
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I think our heater core is the problem, but Im not a professional so I am here...Ha! Anyway... when I turn on the heater, the windows get fogged up and so I bought a heater core thinking that was the problem. But now I have no idea of how to replace this thing so I am asking you?
Aug 19, 2020 at 8:16 PM (Merged)
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BLUELIGHTNIN6
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Heres the best way to describe how to replace heater core in a 2000 blazer..


https://images.2carpros.com/forum/automotive_pictures/261618_Noname_1754.jpg

Aug 19, 2020 at 8:16 PM (Merged)
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MREEP
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Heater problem
2000 Chevy Blazer 6 cyl Four Wheel Drive Automatic 81,ooo miles

I need to replace heater core in 2000 blazer. i have the part but it looks like i have to pull whole dash out. i have had to replace ingine and just replaced the raditor so dont have the money to pay some one to do it. please HELP!!!
Aug 19, 2020 at 8:16 PM (Merged)
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BLUELIGHTNIN6
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https://images.2carpros.com/forum/automotive_pictures/261618_Noname_1999.jpg

Aug 19, 2020 at 8:16 PM (Merged)
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2CP-ARCHIVES
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Heater will not put out heat, checked all the fuses and replaced one 10 amp,,but for some reason water does not seam to be getting to the heater core? any ideas, water relays something like that!!!
Aug 19, 2020 at 8:16 PM (Merged)
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DRCRANKNWRENCH
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There is a heater actuator that lets either coolant in the core and/or opens the vent door for the heat. You will find controlling vacuum pots, cables and actuators on the heater box under the center of the dash. I am attaching instructions for low heat output. When it says heat output test that just menas is it putting out hot air.
Aug 19, 2020 at 8:16 PM (Merged)
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IMTHEWALRUSS
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I just bought a 2000 Chevy S-10 Blazer 4.3L 2WD. The a/c blows really cold but it emits an awful odor and smoke or fog.When I turn the thermostat to a warmer setting, the smoke gets worse. I have flushed the radiator and it does not overheat. It smells a lot like antifreeze. I'm thinking it might be the heater core, but there's no visible leak inside the cab. The smoke comes out through the a/c vents. I don't claim to be good at working on vehicles, but if I can repair this myself and save the cost of having it repaired I will. However, looking in a repair manual at replacing a heater core (if that's even the problem) it seems like quite a task.
Aug 19, 2020 at 8:17 PM (Merged)
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MIKE H R
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check around the hose connections on the firewall first. see if there is any kind of leak. if none found then the heater core is leaking. it is a job to do, it tkes time but one could do it. Check the hoses first. one could be letting it leak go to the inside.
Aug 19, 2020 at 8:17 PM (Merged)
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UNIQUE DIVAH
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How do I put in a heater core? Its leaking antifreeze and putting a black soot on my wind sheild.
Aug 19, 2020 at 8:17 PM (Merged)
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DENNYP
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takes around 7 hours or so. You will need a good service manual. Below is a link to one.
Aug 19, 2020 at 8:17 PM (Merged)
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DAVID KENWARD
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Heater problem
2000 Chevy Blazer 6 cyl Four Wheel Drive Manual

I have to replace the heater core,evry mech. shop around town wants to charge almost $600.00 to do it, saying they have to completly remove the dash to do it. Is this true and if so, is there an easier way I can do it myself at home?
Aug 19, 2020 at 8:17 PM (Merged)
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2CARPRO JACK
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It is true and there is no easy way to go about it, the entire dash has to come out
Aug 19, 2020 at 8:17 PM (Merged)
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TJ DOPORTO
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I would like to know how to open the evaporator box on a the vehicle listed above (s10) in order to change the heater core?
Aug 19, 2020 at 8:18 PM (Merged)
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RASMATAZ
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Hello,

You will need to start by disconnecting the battery and discharging your AC system.

Here are two guides and diagrams with the instructions below.

This will give you an idea.

https://www.2carpros.com/articles/replace-heater-core

Here are the AC instructions:

https://www.2carpros.com/articles/re-charge-an-air-conditioner-system

Check out the diagrams (below). Please let us know if you need anything else to get the problem fixed.

Cheers
Aug 19, 2020 at 8:18 PM (Merged)
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ZEBSHA
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dear sirs, could you please help me by telling me how to change the heater core in my 99 chev blazer
Aug 19, 2020 at 8:18 PM (Merged)
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JACOBANDNICKOLAS
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Hi.
Changing the heater core on your vehicle is an involved procedure. It is located under the dashboard on the passenger side and requires much of the dash to be removed. What I would recommend is that you get a manual for the vehicle. It will provide step by step instructions with pictures to help identify parts.

I would send you the directions, but I am unable to cut and paste from the service manual we use.

If you get a manual and still need some help, let me know. I will be happy to help.

Joe
Aug 19, 2020 at 8:18 PM (Merged)
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BAMAGEOFF
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Hello, I have a 1999 S10 Blazer with 67,000 miles. My heater core began to leak Dexcool into the evaporator box. I flushed it out and by-passed it with a union (Heater core is now unattached from the coolant loop). I took the dash all of the way out of the vehicle to replace the heater core and noticed I needed to remove the heater/evaporator box in order to gain access to the heater core. My question is Instead of taking the evaporator box all of the way out, can I get to the core by cutting the plastic evaporator box, change the core, and plastic weld the evaporator box back together? This would be a major time saver for me if possible.

I appreciate any help you can provide.
Aug 19, 2020 at 8:18 PM (Merged)
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RASMATAZ
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If it is going to work for you playing shortcut do it, but remember if it is not done right, you will be going back in.
Aug 19, 2020 at 8:18 PM (Merged)
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BRIANS1BAD72
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Heater problem
1999 Chevy Blazer 6 cyl Four Wheel Drive Automatic 120k miles

Hello, I have changed the waterpump and thermostat, but still have insufficiant heat. When the car is idleing the heat is luke warm, when you drive the truck you get some heat but not real warm. One thing I have noticed is that the heater hose from the intake to the heater core is hot, the heater hose from the water pump to the heater core is not. You can grab it with your bare hand. Think the heater core is poss. plugged or maybe an air pocket. Thanks for reading, I hope you can help me, Winter is comming.
Aug 19, 2020 at 8:18 PM (Merged)
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2CARPRO JACK
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Sounds like it has a partial restriction. Try having a radiator shop backflush it to free up the clog. Dont use a garden hose, the core can start leaking from too much pressure and you dont want to have to replace the heater core in that Blazer, the entire dash has to come out
Aug 19, 2020 at 8:18 PM (Merged)
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MANCHIS
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how to remove a heater core from a 1999 chevrolet blazer?
Aug 19, 2020 at 8:18 PM (Merged)
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JACOBANDNICKOLAS
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Hi, replacing the heater core is an involved process. You need to remove part of the dashboard. I recommend purchasing a manual for your car. It provides step by step instructions and pictures to help identify parts. I am unable to copy and paste from the online manual we use, and there is too much room for error if I try to explain it via the Internet.
Aug 19, 2020 at 8:18 PM (Merged)
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SUNNY12888
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Heater problem
1999 Chevy Blazer 6 cyl Two Wheel Drive Automatic

im having trouble figuring the easiest way to go about removal of the heater core. any tips? cant get a chiltons right now...
Aug 19, 2020 at 8:18 PM (Merged)
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BMRFIXIT
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Removal & Installation ("C" & "K" Series) Disable air bag system. Disconnect negative battery cable. Remove glove box by squeezing sides together. Remove 2 instrument panel retaining bolts from glove box opening. Remove center floor duct. Remove center support bolt. Remove Electronic Control Module (ECM) and tray. Remove both kick panels. Remove blower motor cover and blower motor. Remove driver's lower instrument panel cover and knee bolster. Lower steering column. Remove instrument panel left and right pivot bolts located at lower corners of instrument panel. Remove 3 screws from defrost vent, near windshield. Disconnect any connectors and tilt instrument panel back far enough to access heater case. Remove coolant recovery reservoir from engine compartment. Drain engine coolant. Disconnect heater hoses at core. Remove bolts and nuts from engine compartment attaching heater case to vehicle. Remove heater case. Remove 7 screws attaching heater case cover plate. Remove screws and bracket attaching core to case. Remove heater core. To install, reverse removal procedure. Replace any seals. Fill cooling system. Start engine and check for leaks. Removal & Installation ("S" & "T" Series) Disconnect negative battery cable. Drain engine coolant. Disconnect heater hoses at core. Remove instrument panel. . Remove air inlet assembly. Disconnect vacuum lines to heater case components. Remove heater case retaining studs from engine compartment. Disconnect blower motor resistor. Remove heater case. Remove heater core access cover from top of heater case. Remove heater core. Remove seals. To install, reverse removal procedure. Fill cooling system. Replace old seals with new seals. Start engine and check for leaks.


https://images.2carpros.com/forum/automotive_pictures/99387_Graphic1_484.jpg


https://images.2carpros.com/forum/automotive_pictures/99387_Graphic2_239.jpg

Aug 19, 2020 at 8:18 PM (Merged)
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SHUGMISSEY
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had my heater core replaced and now have no heat. What could be the problem?
Aug 19, 2020 at 8:18 PM (Merged)
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MADMIKE1735
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Most likely an air pocket not allowing coolant to reach the heater core lines. Run the vehicle until it reaches around 200 degrees, that will allow the thermostat to open. Then let it cool off for a while before checking the coolant level. Add as necessary.
Aug 19, 2020 at 8:18 PM (Merged)
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SORICH1
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good you please show me a diagram or explanation of the removal of the heating ventilation module?

thank you
Aug 19, 2020 at 8:18 PM (Merged)
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WRENCHTECH
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Believe me, this is not something that you even want to attempt. This is a major undertaking. Even for an experienced tech, this is about a ten hour job.

This involves removing the entire dash and part of the fender to get this apart. There are many experienced techs that will not attempt this.
Aug 19, 2020 at 8:18 PM (Merged)
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MADMIKE1735
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I could not have said it better myself. Wrenchtech is 150% correct with this one. The book time give 8.9 hours. That is giving a professional tech is doing the job. I have done a few, and hated each one, haha. Keep in mind, before the dash comes out, you need to disable, and remove the air bags, one wrong move, and they may deploy causing serious injuring. Leave this job to the professionals.
Aug 19, 2020 at 8:18 PM (Merged)
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JOHNADAMS1
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I have a 99 Chevy Trailblazer s10. I... Any suggestions? I took the dash back apart and reconnected the wiring and it started and ran for a few days, but now it will turn over but not start?
Aug 19, 2020 at 8:18 PM (Merged)
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KHLOW2008
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https://www.2carpros.com/articles/car-cranks-but-wont-start

You need to find out what is missing causing the non starting.
Aug 19, 2020 at 8:18 PM (Merged)
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DIXIE_ETTORE
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I replaced the heater core in my truck over the weekend. Now, all of the gauges except for my speedometer don't work. Also my heat still doesn't work. I have no way to judge how much gas is in it, or to see if it's still overheating. Is there a way to fix this?
Aug 19, 2020 at 8:19 PM (Merged)
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JOHNNYT73
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It could be that your hvac control head is bad. Remove it and see if any of the connectors are melted. Then check to see if your blend door actually moves. Your cluster may need replacing. Check to make sure you got all the connections in the right place and and check fuses.
Aug 19, 2020 at 8:19 PM (Merged)
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