S10 Heater Core

Discussion in '4X4 Truck Talk and Repairs' started by cantstopgrandma, Jan 3, 2011.

  1. cantstopgrandma

    cantstopgrandma New Member

    Got a 98 s10, noticed coolant smell in cab this morning. Windshield fogged up after sitting at work a couple hours. I think the heater core is toast. Anybody got any experience with this repair? Looks like the whole dash has to come out, and I'm thinking this would be a good job for someone else. I would like opinions on said repair before i spend the $$$$. Its a shame it costs so much to replace a $60 part.
     
  2. It don't matter what vehicle you got, it's a pain in the *** no matter what.
     

  3. crazyjet1

    crazyjet1 New Member

    Man im in the same boat mine is out In my f150 went out when i was in south catolina. The fog on the winshield was pain n my arse. Had drive all 700 miles
    Home with window down i froze.
     
  4. bluejay

    bluejay Well-Known Member

    On the older Fords it is behind the glove box and easy to get to. Not sure about the newer ones.
     
  5. Holmes

    Holmes New Member

    yep the whole dash has to come out. bout a 8 hr job.
     
  6. Your looking at $400 if your lucky.
     
  7. Depends on the year but there was a class action lawsuit on the Dexcool that was remimbursing a good portion of coolant system repairs.
    I don't know if it's expired or what but it wouldn't be hard to find on the net.

    Biggest thing with those vehicle being that so much is aluminum is running the recommended anti freeze. Don't put the green in them.
    They've had alot of heater core, water pump, and head gasket issues in the Vortec V6 in some of those years.
    Alot of it is caused by folks not running the right coolant according to my GM certified mechanic. You can't run just any ol coolant with aluminum engine components as the aluminum will pit.
     
  8. Sorry to hear about your problem. Will be interested in hearing what you do as I have the same 98 truck and engine. Best of luck.
    :glasses-cool:
     
  9. i have a olds bravada my heater core is clogging up not putting out much heat started in on the fix last week got front of dash tore out and still could not get to it! guess next step is figurring out how to drop the whole dash down but think i will try a flush first not looking forwerd to pulling dash ! the coolent in it is the nastyest looking stuff i ever seen!
     
  10. That is why alot of folks make the mistake of going to green antifreeze and then the real problems start.
    Best thing to do with the red stuff is flush it periodically. I put on average 40,000 miles a year on a vehicle. I have my system flushed once a year.

    The way these vehicles are now, you are ahead of the game if you stick to the manual.

    When it comes to oil however I use Amsoil with Amsoil filters.
     
  11. cantstopgrandma

    cantstopgrandma New Member


    My truck has always had Dex-Cool in it. Still having issues....

    I pressure tested cooling system yesterday after work, and there is a slow leak somewheres. I didn't have any smell or fogging this morning, so now i'm not sure what's going on. For now, i'm carrying a nipple and some extra hose clamps in case of catastrophic failure of the heater core. I guess time will tell.
    Bad thoughts running thru my head......thinking about buying a ford next time ***GASP*** I thought ford was supposed to be fix or repair daily, but seems like i'm constantly working on, or having someone else work on my 2 chevys. :at-wits-end:
     
  12. Dallas I read your post. My heater core in my 2001 Blazer was plugged real good to the point it would heat a little for a few minutes then nothing. The inlet is 3/4 the outlet is 5/8/ Go get yourself 2 pieces of clear plastic hose a foot long. 1 of them 3/4" the other 5/8" and get a brass garden hose repair barb for each hose and 4 hose clamps. hook your garden hose up to the outlet side and turn the water on slowly. With the other clear hose hooked up to the inlet side you'll be able to watch the crud come out. Don't use full blast pressure in it until it is unclogged or you will blow a whole in it. Once it is flowing real good crimp your garden hose until it builds up some pressure and let it rip, you'll see some more crud come out. do that a few times. Flush the whole system real good before you hook the heater core back up to drive it. Mine works so good now it will burn you out of there.
     
    BIG_D likes this.
  13. Imagine that! LOL Here's some technical info:


    REMOVAL PROCEDURE





    Remove the instrument panel. See: Body and Frame\Interior Moulding / Trim\Dashboard / Instrument Panel
    Drain the engine coolant.
    On vehicles with automatic climate control only, cut the outer layer of the A/C evaporator and blower module in order to access the service access cover.




    On vehicles with automatic climate control only, remove the service access cover mounting screws (1).
    On vehicles with automatic climate control only, remove the service access cover (2).
    On vehicles without automatic climate control, remove the blower motor resistor. Refer to Blower Motor Resistor Assembly Replacement (C42) or Blower Motor Resistor Assembly Replacement (C60).
    IMPORTANT: Mark and use the same mounting bolt for the heater/vent module during the installation process. Other mounting bolts are longer and will obstruct the operation of the temperature door.

    Remove the heat/vent module mounting bolt through the blower motor resistor or service access cover opening.




    On vehicles with A/C only, remove the right wheel house panel. Refer to Wheelhouse Panel Replacement in Body Front End.
    On vehicles with A/C only, raise and support vehicle. Refer to Vehicle Lifting in Maintenance.
    On vehicles with A/C only, remove the front right tire. Refer to Tire and Wheel Removal and Installation in Tires and Wheels.
    On the Utility only, remove the A/C evaporator and blower module heat shield screws.
    On the Utility only, slide the A/C evaporator and blower module heat shield toward the front of the vehicle.
    Remove the 2 lower heat/vent module mounting nuts.
    On the Utility only, remove the A/C evaporator and blower module heat shield bracket.





    Remove the bottom right heat/vent module mounting bolt from inside the vehicle.
    IMPORTANT: The heat/vent mounting stud has a flange on the inside and cannot be removed from under the hood. Stop turning the stud after the threads are off the heat/vent module.

    On the Utility only, while an assistant inside the vehicle pulls the bottom right corner of the heat/vent module approximately 2.5 mm (1 in) back, remove the 2 heat/vent module mounting studs.
    On vehicles with A/C only, lower the vehicle.
    On vehicles with a 2.2L engine only , remove the engine wiring harness bracket located at the rear of the intake manifold. Refer to Valve Rocker Arm Cover Replacement in Engine - 2.2L.
    Remove the HVAC module mounting bolt located at the lower left side of the heater core to heater hose connection.
    Remove the HVAC module mounting nut located at the lower right side of the heater core to heater connection.
    IMPORTANT: The heat/vent mounting stud has a flange on the inside and cannot be removed from under the hood. Stop turning the stud after the threads are off the heat/vent module.

    On the utility models only , loosen the HVAC module mounting studs until the threads are free from the heat/vent module.
    Disconnect all of the electrical connectors from the HVAC module.
    Disconnect all of the vacuum lines from the heater assembly.
    Disconnect the heater hoses from the heater core.
    Remove the HVAC module from the vehicle.
    INSTALLATION PROCEDURE





    If replacing the HVAC module, transfer the components from the old heat/vent module as necessary.
    IMPORTANT: Before installing the HVAC module to the vehicle, ensure that the HVAC module mounting studs are located in the proper positions.

    Install the HVAC module to the vehicle.
    Connect the heater hoses to the heater core.
    Connect all of the vacuum lines to the heater assembly.
    Connect all of the electrical connectors to the HVAC module.
    Install the bottom right HVAC module mounting bolt from inside the vehicle approximately halfway into the threads.
    NOTE: Refer to Fastener Notice in Service Precautions.

    On the Utility only, install the HVAC module mounting stud located at the lower right side of the heater core to heater hoses connection in the engine compartment.
    Tighten the HVAC module mounting stud to 4.5 N.m (40 lb in) .

    On vehicles with A/C only, raise the vehicle. Refer to Vehicle Lifting in Maintenance.
    On the Utility only, install the bottom right HVAC mounting studs. Ask an assistant to pull the bottom right corner of the HVAC module back from inside the vehicle.
    Tighten the heat/vent module mounting studs to 4.5 N.m (40 lb in) .

    On the Utility only, install the A/C evaporator and blower module heat shield bracket.
    Install the heater/vent module mounting nuts.
    Tighten the HVAC module mounting nuts to 4.5 N.m (40 lb in) .

    On the Utility only, slide the A/C evaporator and blower module heat shield into the original position.
    On the Utility only, install the A/C evaporator and blower module heat shield screws.
    Tighten the A/C evaporator and blower module heat shield screws 2.2 N.m (19 lb in) .





    On vehicles with A/C only, install the right front tire. Refer to Tire and Wheel Removal and installation in Tires and Wheels.
    On vehicles with A/C only, lower the vehicle.
    Install the bottom right HVAC module mounting bolt from inside the vehicle.
    Tighten the HVAC module mounting bolt to 4.5 N.m (40 lb in) .

    On vehicles with A/C only, install the right wheel house panel. Refer to Wheelhouse Panel Replacement in Body front End.




    Install the HVAC module mounting nut located at the lower right side of the heater core to heater connection.
    Tighten the HVAC module mounting nut to 4.5 N.m (40 lb in) .

    Install the HVAC module mounting bolt located at the lower left side of the heater core to heater hose connection.
    Tighten the HVAC module mounting bolt to 4.5 N.m (40 lb in) .

    On vehicles with the 2.2L engine only, install the engine wiring harness bracket located at the rear of the intake manifold. Refer to Valve Rocker Arm Cover Replacement in Engine - 2.2L.
    IMPORTANT: Use the same mounting bolt marked during removal for the HVAC module during the installation process. Other mounting bolts are longer and will obstruct the operation of the temperature door.





    Install the HVAC module mounting bolt through the blower motor resistor or service access cover opening.
    Tighten the HVAC module mounting bolt to 4.5 N.m (40 lb in) .

    On vehicles without automatic climate control, install the blower motor resistor. Refer to Blower Motor Resistor Assembly Replacement (C42) or Blower Motor Resistor Assembly Replacement (C60).
    On vehicles with automatic climate control only, install the service access cover (2).
    On vehicles with automatic climate control only, install the service access cover mounting screws (1).
    Tighten the screws to 1.9 N.m (17 lb in) .





    On vehicles with automatic climate control only, install the outer layer of the A/C evaporator and blower module.
    IMPORTANT: Do not use RTV. Apply the adhesive bead as straight as possible. Allow the adhesive to set for 15 minutes or until the adhesive becomes tacky.

    Seal the cut line using black weather-strip adhesive.
    Refill the engine coolant. Refer to Draining and Filling Cooling System in Cooling System.
    Install the instrument panel.
    Calibrate the HVAC module actuator. Refer to Re-Calibrating Actuators in HVAC Systems - Automatic.
     
  14. that sounds like a job for a professional gluton
     
  15. Here's the dash removal proc. I'll try to add a couple pic's so it don't look greek.
    Instrument Panel Assembly Rotating

    REMOVAL PROCEDURE

    85128827.gif


    On vehicles equipped with a manual transmission, remove the shift lever.
    On vehicles equipped with an automatic transmission, perform the following steps:
    2.1. Apply the park brake.
    2.2. Insert the ignition key and turn the ignition switch to the RUN position.
    2.3. Depress the brake pedal and shift the transmission to the 1 position.
    2.4. Turn the ignition switch to the OFF position.
    CAUTION: Refer to Battery Disconnect Caution in Cautions and Notices.

    Disconnect the battery negative cable.
    Remove the left sound insulator.
    Remove the right instrument panel sound insulator.
    If the vehicle is equipped with a multiple CD changer located in the center console, remove the center console.
    Remove the center sound insulator.
    Remove the lower left instrument panel mounting bolt.
    Remove and retain the instrument panel storage compartment.
    Remove the lower right instrument panel mounting bolt.
    85128828.gif



    Remove and retain the left and right speakers and the speaker grilles.
    Use a flat-bladed tool in order to remove the windshield defroster grille. Retain the grille and sunload sensor for use on the next IP carrier.




    If equipped with a sun load temperature sensor twist the sensor 1/4 turn counterclockwise in order to disengage.
    Disconnect the brown electrical connection from the body control module (BCM).
    Disconnect the purple electrical connection from the body control module (BCM).
    Remove the knee bolster.
    Remove and retain the instrument cluster.
    Remove and retain the radio.
    Remove the HVAC control assembly.
    CAUTION: Refer to SIR Handling Caution in Cautions and Notices.

    Disable the passenger side SIR system.




    Remove the left and right instrument panel driver knee bolster brackets.
    Lower the steering column for clearance.

    85128831.gif



    IMPORTANT: Label all of the connections in order to avoid improper installation.

    Remove the top instrument panel screws.
    Roll the instrument panel down.
    Disconnect the electrical connections, as needed.
    Remove the fastener that retains the radio antenna cable to the instrument panel.
    Remove the instrument panel from the vehicle. If replacing the instrument panel carrier, retain the parts for assembly of the new instrument panel carrier.
    INSTALLATION PROCEDURE




    Install the retained parts from the original instrument panel.
    Install the instrument panel to the vehicle.
    Install the fastener that retains the radio antenna cable to the instrument panel.
    Tighten
    Tighten the fastener to 1.9 N.m (17 lb in) .

    Connect the electrical connectors, as needed.
    Roll the instrument panel up.
    Install the top instrument panel screws.
    Tighten
    Tighten the screws to 1.9 N.m (17 lb in) .





    Raise the steering column into position.
    Install the left and right instrument panel driver knee bolster brackets.
    Tighten
    Tighten the screws/bolts to 6.3 N.m (56 lb in).





    Enable the passenger side SIR system.
    Install the HVAC control assembly to the instrument panel.
    Install the radio.
    Install the instrument cluster.
    Install the knee bolster.
    Connect the purple electrical connection to the body control module (BCM).
    Connect the brown electrical connection to the body control module (BCM).
    If equipped with a sun load temperature sensor, install the sensor to the defroster grille by twisting the sensor 1/4 turn clockwise.




    Install the windshield defroster grille by pressing carefully pressing the grille into place.
    Install the left and right speakers and the speaker grilles.




    Install the lower right instrument panel mounting bolt.
    Tighten
    Tighten the bolt to 11.5 N.m (102 lb in).

    Install the instrument panel storage compartment.
    Install the lower left instrument panel bolt.
    Tighten
    Tighten the bolt to 11.5 N.m (102 lb in).

    Install the center sound insulator.
    Install the right sound insulator.
    If the center console was removed, install the console to the vehicle.
    Install the left sound insulator.
    Connect the battery negative cable.
    On vehicles equipped with an automatic transmission, perform the following steps:
    27.1. Turn the ignition switch to the RUN position.
    27.2. Depress the brake pedal and shift the transmission into the PARK position.
    27.3. Release the park brake.
    On vehicles equipped with a manual transmission, install the shift lever.
     
  16. And last but not least, Have fun !
     
  17. I just read this. I missed it the first time I read the thread. If your truck has a 4.3 vortec, and there's a mysterious coolant loss. I would bet the farm it had an intake leaking. There's one positive. It's slowly steam cleaning your pistons! Does it ever miss a little on a cold start? Most likely with the fogging issues it had, you have a couple of problems. Buy a ford or a dodge. G.M. has fallen off the map in my eyes.........
     
  18. cantstopgrandma

    cantstopgrandma New Member


    Intake was already done once (not to say it couldn't be leaking again)..... my wife's car too, hence my hatred for GM. I'll never own a dodge, i'll buy another chevy first.
     
  19. cantstopgrandma

    cantstopgrandma New Member


    kinda what i was thinking.
     
  20. Holmes

    Holmes New Member

    ford and dodge same thing. one is a for focus and one is a dodge durango. can u tell them apart? lol got a ford explorer to do this week too.

    dont realy matter what antifreeze you use as long as u change it every other year no mater what it says on the bottle. then agin i like it when people dont. gives me something to do. lol
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