1. Welcome to Tacoma World!

    You are currently viewing as a guest! To get full-access, you need to register for a FREE account.

    As a registered member, you’ll be able to:
    • Participate in all Tacoma discussion topics
    • Communicate privately with other Tacoma owners from around the world
    • Post your own photos in our Members Gallery
    • Access all special features of the site

Air bubble in heater core

Discussion in '2nd Gen. Tacomas (2005-2015)' started by Nalpak99, Jan 9, 2021.

  1. Jan 9, 2021 at 11:38 AM
    #1
    Nalpak99

    Nalpak99 [OP] Booty Hunter

    Joined:
    Mar 17, 2020
    Member:
    #322343
    Messages:
    88
    Gender:
    Male
    First Name:
    Kyle
    Vehicle:
    2005 Toyota Tacoma pre-runner
    3” lift, pod lights, police siren, garage door opener, led interior lights, radio, backup camera.
    When I first turn on my car and start driving I can hear the coolant moving underneath my steering wheel. I’m pretty sure this means that there is an air bubble in my heater core. I have no overheating issues. What’s the best way to bleed it?
     
  2. Jan 9, 2021 at 12:22 PM
    #2
    TnShooter

    TnShooter Well-Known Member

    Joined:
    Sep 2, 2010
    Member:
    #42625
    Messages:
    4,490
    Gender:
    Male
    Vehicle:
    07' TRD Off-Road, Auto
    STOCK
    I use a “Spilll-Free” funnel.
    Run the engine with the heat on High and fan speed on Med or High.
    Squeeze both the upper and lower hoses while the truck is warming up.
    Some guys like to park the truck with the FRONT END on an incline. (Up hill).
    This helps get heater core down lower and the radiator up higher. (Air rises)
    I personally haven’t had to do this with my truck. But it does help.

    You don’t have to use the funnel. But it makes a lot less of mess if you do.
    https://www.amazon.com/Lisle-24680-Spill-Free-Funnel/dp/B00A6AS6LY
     
    BassAckwards and Lester Lugnut like this.
  3. Jan 9, 2021 at 2:50 PM
    #3
    fixnfly

    fixnfly Well-Known Member

    Joined:
    Oct 1, 2011
    Member:
    #64450
    Messages:
    566
    Gender:
    Male
    First Name:
    Mike
    S.W.PA
    Vehicle:
    05 Access cab 4.0 4WD
    Was the coolant system opened up recently?
     
  4. Jan 9, 2021 at 3:10 PM
    #4
    Plain Jane Taco

    Plain Jane Taco I have become comfortably numb

    Joined:
    Apr 19, 2009
    Member:
    #16179
    Messages:
    26,637
    Gender:
    Male
    First Name:
    Bill
    USA
    Vehicle:
    2015 SW DCSB TRD Sport PR
    One of the most common no-no's people do when refilling the radiator is pouring it in quickly. That will trap more air and take longer to purge. Always pour the coolant in very slowly and pause every few seconds. This will purge alot the air as you go. Be sure to do this BEFORE you start the engine. You want as much coolant and as little air in the system before the pump starts sloshing things around.

    Also....be sure to have the radiator cap off and let it idle for a while. This will purge much of the remaining air. And as mentioned....make sure the heat is on.

    You may need to adjust your reservoir a day or 2 later, as the system will pull from it as it cools
     
    BassAckwards and Lester Lugnut like this.
  5. Jan 9, 2021 at 8:12 PM
    #5
    Jimmyh

    Jimmyh Well-Known Member

    Joined:
    May 16, 2012
    Member:
    #78991
    Messages:
    11,810
    Gender:
    Male
    SC
    Vehicle:
    2012 Prerunner SR5

    What purpose does that serve? Coolant always flows through the heater core, there is no coolant valve.
     
  6. Jan 9, 2021 at 8:15 PM
    #6
    Plain Jane Taco

    Plain Jane Taco I have become comfortably numb

    Joined:
    Apr 19, 2009
    Member:
    #16179
    Messages:
    26,637
    Gender:
    Male
    First Name:
    Bill
    USA
    Vehicle:
    2015 SW DCSB TRD Sport PR
    To ensure that coolant is flowing properly through the core. If you have heat you know it's flowing. The core is the most likely place for an air pocket to lodge in
     
    RedWings44 likes this.
  7. Jan 9, 2021 at 8:18 PM
    #7
    Jimmyh

    Jimmyh Well-Known Member

    Joined:
    May 16, 2012
    Member:
    #78991
    Messages:
    11,810
    Gender:
    Male
    SC
    Vehicle:
    2012 Prerunner SR5
    I usually just feel the inlet and outlet pipes down by the accelerator pedal. Both should be hot.
     
  8. Jan 9, 2021 at 8:25 PM
    #8
    Plain Jane Taco

    Plain Jane Taco I have become comfortably numb

    Joined:
    Apr 19, 2009
    Member:
    #16179
    Messages:
    26,637
    Gender:
    Male
    First Name:
    Bill
    USA
    Vehicle:
    2015 SW DCSB TRD Sport PR
    Simple to roll down the driver's window with the heat on. While it's idling with the cap off you can reach in and feel the air
     
  9. Jan 9, 2021 at 9:33 PM
    #9
    6 gearT444E

    6 gearT444E CEO & CFO @BPF

    Joined:
    Feb 3, 2018
    Member:
    #243372
    Messages:
    2,528
    Deep South
    Herculiner Hootus
    Park on an incline like a hill or some ramps, remove radiator cap, start up truck. I like to massage the coolant pipes as well it helps to move any pockets of air. Don’t be afraid to let it idle for a while, it takes some time to get all the air out.
     
    Plain Jane Taco and Wyoming09 like this.
  10. Jan 10, 2021 at 1:14 AM
    #10
    jboudreaux1965

    jboudreaux1965 Ragin Cajun Fan

    Joined:
    Jun 2, 2014
    Member:
    #131162
    Messages:
    3,110
    Gender:
    Male
    First Name:
    Joseph
    Hub City
    Vehicle:
    2006 Pre-Runner TRD Sport
    2005 to 2012 Front End Mod 3" 810lb IronMan TOYO50C coils 4" MaxTrac Spingles 35.6"x 12.8" Amp Off-road A/T PPro Dodinson front struts and rear shocks Deaver AAL Custom 4" Aluminum single piece driveshaft 2012 Interior 2009 J-VIN Japanese made 1GR-FE Cali Off-road Anarchy PVD wheels 20"x10" etc.... Lol!
    Do you want an honest answer....

    its a 2005, look on the door sticker, if the manufacturer date is before 12/2005 it shipped with defective head gaskets. the bubbles in the heater core are the first sign that the defective piece of the gasket between cyl 4 and 6 is getting weak. what is happening is the gasket has not failed enough to have a constant leak. when the engine is good and hot and the RPM's get high for a second exhaust gas is pushed through into the coolant which gets trapped in the heater core. then after you let it set over night when you start it you hear the bubbles get flushed out. you have between 3000 and 10000 miles before you have bubbles coming out your overflow and over heating starts. of course try all the other options first, bleeding, etc... after you do all of that the bubbles WILL stop. depending on how you drive and how much you drive, after you get the bubbles to stop i predict in about 10-14 days the bubbles come back. if so you need to make a decision. you can put some Barr's sealant in it (the expensive version and follow the directions to the letter) and drive the truck for about 12-18 months depending on how much you drive before you have to either replace the engine or pull your current engine, clean all the sealant out, replace the hoses and radiator, etc to make sure the sealant is out of the system and replace the head gaskets or bite the bullet and replace the head gaskets or just put Barr's in it and sell or trade in the truck.

    sorry for the bad news :(

    usually bubbles start around 135000 miles +/- 20000 miles, how many miles on the truck?
     
    Last edited: Jan 10, 2021
    Athlaos and scottalot like this.
  11. Jan 10, 2021 at 4:13 AM
    #11
    jboudreaux1965

    jboudreaux1965 Ragin Cajun Fan

    Joined:
    Jun 2, 2014
    Member:
    #131162
    Messages:
    3,110
    Gender:
    Male
    First Name:
    Joseph
    Hub City
    Vehicle:
    2006 Pre-Runner TRD Sport
    2005 to 2012 Front End Mod 3" 810lb IronMan TOYO50C coils 4" MaxTrac Spingles 35.6"x 12.8" Amp Off-road A/T PPro Dodinson front struts and rear shocks Deaver AAL Custom 4" Aluminum single piece driveshaft 2012 Interior 2009 J-VIN Japanese made 1GR-FE Cali Off-road Anarchy PVD wheels 20"x10" etc.... Lol!
    a tip.... if you need to maximize time before you do anything major, you can run it until you get a check engine light with error code cyl 6 misfire before you either fix it or put Barr's in it. once you get a misfire on 6 gasket is about to go.
     
  12. Jan 10, 2021 at 4:49 AM
    #12
    scottalot

    scottalot FooW

    Joined:
    Jun 1, 2013
    Member:
    #105349
    Messages:
    124,357
    Gender:
    Male
    First Name:
    Stockalot
    SC
    Vehicle:
    2018 tea four arghh Offroad 4x4 White LoveMachine
    Bone stock like Chicken in the Crock Pot .Dakkars,305/70/16 MT's, Extended length Fox Coilovers, Fox RR rear Shocks, Total Chaos UCA's, Dakar Leaf packs, LED Map and Dome, Breather relocate, Slimer from Ghost-busters starut up screen, Vent Visors, LED Pod's on Ditch Brackets soon, Level 8 Strike 6 Wheels, New MT Tars - Fierce Attitude, SOS front bumper -steel, SOS bed rack, LED white marker lights, LED reverse, TRD exhaust, Wheelers Super Bumps up front, SOS sliders bolt on with fill plates, Csjummper2003 White/Amber DTRL and white parking led bulbs, RTT rack basket Sold 2013, sold 2014 Tacoma. All listed stuff was on the '14 Bed Mat, WeatherTech Rain Guards, Ultra Gauge, TW Sticker amongst others, Useless Free OEM Bug Deflector, Flyzeye, OME Kit with 885's and Dakar and Nitro Shocks front and Rear . Tailgate mod, SOS Concepts 1/4" Skid Plate, White LED's interior Dome and Maps, Goodyear Wrangler MTR Kevlar 275/70/17, Wet Okole Seat Covers - full piping in Charcoal Grey, Lamin-X Green Fog light film, 17"x8 -10 offset Level 8 MK6 wheels in Gun Metal Finish, SOS Concepts Sliders W/ Kickout 12/21/14, Stubby antenna, LED reverse lights, lift removed 2/20/15 - making changes and trying to make up my mind
    I’m gonna say you’re not much of a desserts guy.... cause ya sure didn’t sugar coat that reply :laugh:

    imho- these are the replies I like. Blunt and straight forward. May or may not be the case for the op but it clears the dust in the air and lays out what could be worse case. Kinda like going to the doctor- give to me straight forward
     
    BassAckwards, Jimmyh and CurtB like this.
  13. Jan 10, 2021 at 5:48 AM
    #13
    Too Stroked

    Too Stroked Well-Known Member

    Joined:
    Jan 24, 2017
    Member:
    #208501
    Messages:
    2,189
    Gender:
    Male
    First Name:
    Tom
    South shore of Lake Ontario
    Vehicle:
    2014 Tacoma TRD Sport 4x4
    Remember, on older vehicles, the amount of heat coming out of the heater / defroster ducts was controlled by a valve that regulated the coolant flow through the heater core. On almost all newer vehicles, it works differently. Coolant flows through the heater core constantly, but the amount of heat coming out of the heater / defroster ducts is controlled by a blend door that regulates the amount of air going past the heater core. So in newer vehicles, cranking the heat all the way up has no effect on the amount of coolant flowing through the heater core.

    BTW, I'm surprised nobody has picked up on the fact that the OP says he's hearing gurgling "under the steering wheel." The Heater Core is on the passenger side last time I checked.
     
    SR-71A likes this.
  14. Jan 10, 2021 at 5:52 AM
    #14
    6 gearT444E

    6 gearT444E CEO & CFO @BPF

    Joined:
    Feb 3, 2018
    Member:
    #243372
    Messages:
    2,528
    Deep South
    Herculiner Hootus
    this is true. Perhaps that gurgling is an old girlfriend trying to win him back :rofl:
     
    BassAckwards and hx989 like this.
  15. Jan 10, 2021 at 8:17 AM
    #15
    Lester Lugnut

    Lester Lugnut Well-Known Member

    Joined:
    Mar 3, 2010
    Member:
    #32477
    Messages:
    2,827
    Gender:
    Male
    N of Mex-S of Canada-E of LA-W of NC
    Vehicle:
    '15 Tacoma PreRunner V6 SR5 Auto
    Yep
     
  16. Jan 10, 2021 at 12:33 PM
    #16
    TnShooter

    TnShooter Well-Known Member

    Joined:
    Sep 2, 2010
    Member:
    #42625
    Messages:
    4,490
    Gender:
    Male
    Vehicle:
    07' TRD Off-Road, Auto
    STOCK
    @Jimmyh

    You are correct. And I actually thought of that while writing my response.
    The main reason is #3 below.

    The reasons I mentioned it in my post above was for a few reason.

    1. The factory FSM says;
    Fan Speed = Anything except OFF
    Heat = Towards Warm
    AC = OFF

    2. This method is pretty safe to use on MOST other vehicles as well.
    (You can help your buddy who doesn’t have a Tacoma or new vehicle, and still be ok doing this)

    3. If I didn’t mention it, I was quite sure someone would tell me I was incorrect.
    (Since the FSM say to) :rofl:

    Like the old saying goes, If you want the correct answer to a problem.
    Give the Wrong answer. You’ll soon be corrected.

    Again, I do agree with you.
    As you are correct, there’s really no need to have the heat or fan on while filling the cooling system.
    The fan could actually make the process take longer.

    The important thing to watch it the TEMPERATURE.
     
    CurtB and Jimmyh like this.
  17. Jan 10, 2021 at 12:36 PM
    #17
    TnShooter

    TnShooter Well-Known Member

    Joined:
    Sep 2, 2010
    Member:
    #42625
    Messages:
    4,490
    Gender:
    Male
    Vehicle:
    07' TRD Off-Road, Auto
    STOCK
    I believe it more centered on the Tacoma.
    I haven’t actually pulled the dash apart to look though.
    I hope I NEVER have to. I’ve done a total of 3 cores in my lifetime.
    The 1st one was enough to do me.

    upload_2021-1-10_15-36-43.jpg
     
  18. Jan 10, 2021 at 7:34 PM
    #18
    Jimmyh

    Jimmyh Well-Known Member

    Joined:
    May 16, 2012
    Member:
    #78991
    Messages:
    11,810
    Gender:
    Male
    SC
    Vehicle:
    2012 Prerunner SR5
    Yes it is nearly exactly in the center and the inlet / outlet piping is on the drivers side which is probably the source of the sound.
     
    Too Stroked and TnShooter like this.
  19. Jan 11, 2021 at 11:06 AM
    #19
    Nalpak99

    Nalpak99 [OP] Booty Hunter

    Joined:
    Mar 17, 2020
    Member:
    #322343
    Messages:
    88
    Gender:
    Male
    First Name:
    Kyle
    Vehicle:
    2005 Toyota Tacoma pre-runner
    3” lift, pod lights, police siren, garage door opener, led interior lights, radio, backup camera.
    I definitely drive my truck hard. It has 200k miles on it. I can 100% replace the head gasket but will that fix the problem?
     
  20. Jan 11, 2021 at 11:11 AM
    #20
    RedWings44

    RedWings44 Well-Known Member

    Joined:
    Apr 28, 2020
    Member:
    #326226
    Messages:
    2,614
    Gender:
    Male
    Michigan
    Vehicle:
    2017 Black TRD Off Road 4x4
    Cooper Discoverer AT3 4S (kind of a mod)
    Don't go changing head gaskets unless you know you have a problem. Do you have issues with your heat? Have you checked the coolant levels? If you have a head gasket issue, your heater core isn't likely to be your only problem. Start with the simpler stuff first and work on diagnosis.
     
    b_r_o and Too Stroked like this.

Products Discussed in

To Top