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

Best place to splice into the cooling system

Discussion in '1st Gen. Tacomas (1995-2004)' started by EntradaTaco, Apr 2, 2012.

  1. Apr 2, 2012 at 1:56 PM
    #1
    EntradaTaco

    EntradaTaco [OP] Member

    Joined:
    Feb 23, 2012
    Member:
    #73437
    Messages:
    9
    Gender:
    Male
    First Name:
    Brandon
    Utah
    Vehicle:
    04 SR5 TRD
    Grey Wire, ABS Switched, DRL Switched, Auxiliary Fuse Block, Hella Driving + Fog Lights, Backup Lights
    I'm installing an on-board hot water supply and hydronic cabin heater in the bed of my truck. I'm trying to determine where the best place to splice into the cooling system would be.

    Locations I've considered are between the radiator and oil pump, or the exit side of the heater core. I know little about the cooling systems path of travel in the vehicle and these locations may not ever be feasible :notsure:

    Any thoughts or ideas?
     
  2. Apr 2, 2012 at 2:05 PM
    #2
    4wd Boss

    4wd Boss Shake and Bake

    Joined:
    Jan 19, 2012
    Member:
    #70978
    Messages:
    340
    Gender:
    Male
    First Name:
    Jefferson
    Big D
    Vehicle:
    07 4dr 4x4 V6
    Fog Light Mod
    why would you need a hydronic heater in a pickup? puttin on a camper and plan on sleeping in there many a freezing night? Is the hot water tap part of your heater system or for other uses? all sounds very risky to me. I would say whatever you do, make sure its at a location that is easily accessed, in case a leak were to spring.
     
  3. Apr 2, 2012 at 3:38 PM
    #3
    EntradaTaco

    EntradaTaco [OP] Member

    Joined:
    Feb 23, 2012
    Member:
    #73437
    Messages:
    9
    Gender:
    Male
    First Name:
    Brandon
    Utah
    Vehicle:
    04 SR5 TRD
    Grey Wire, ABS Switched, DRL Switched, Auxiliary Fuse Block, Hella Driving + Fog Lights, Backup Lights
    Actually, that's exactly what I've been doing, all winter long. The heated cooling system is used to heat the cabin with the hydronic accessory heater and the water using a plate heat exchanger. I plan to install a diversion manifold in the engine bay to bypass the lines going to the bed... just in case.
     
  4. Apr 2, 2012 at 3:41 PM
    #4
    OZ-T

    OZ-T Quite an experience to live in fear , isn't it ?

    Joined:
    Dec 15, 2009
    Member:
    #27584
    Messages:
    38,727
    Gender:
    Male
    First Name:
    Peter North
    British Columbia
    Vehicle:
    Mag Grey 09 Trd Sport DCLB 4x4
    OME 885x , OME shocks and Dakars , Wheelers SuperBumps front and rear , 275/70/17 Hankook ATm , OEM bed mat , Weathertech digifit floor liners , Weathertech in-channel vents , headache rack , Leer 100RCC commercial canopy , TRD bedside decals removed , Devil Horns by Andres , HomerTaco Satoshi
    Interesting system
     
  5. Apr 2, 2012 at 5:14 PM
    #5
    hayabusa3303

    hayabusa3303 Well-Known Member

    Joined:
    Aug 3, 2011
    Member:
    #61062
    Messages:
    556
    Gender:
    Male
    First Name:
    Mike
    florence sc
    Vehicle:
    95.5 taco 4x4
    ARB bumper, warn 9.5 winch. carbon fiber hood. Leer top with thule racks and MOAB from thule. Electric fans, blue sea fuse block, Sony dvd Head unit, Xm tuner and HD tuner. New carpet and new racing seats. ( other half doesnt like them i think). Nwor springs and adjustable coil overs. Sky jacker rear shocks. Slot and drilled rotors. Engine Titanium ceramic coated headers, no cat, jba cat back. URD Rear Sensor Simulator. Leds all around and inside cab and HID H4 hi/lo beams.
    I believe i know what your talking about here.

    Best place would be after the heater bypass use a T or a Y fitting there and on the return use a T or a Y fitting just passed the heater also.

    Imo dont splice into your rad hoses.
     
  6. Apr 2, 2012 at 5:28 PM
    #6
    EntradaTaco

    EntradaTaco [OP] Member

    Joined:
    Feb 23, 2012
    Member:
    #73437
    Messages:
    9
    Gender:
    Male
    First Name:
    Brandon
    Utah
    Vehicle:
    04 SR5 TRD
    Grey Wire, ABS Switched, DRL Switched, Auxiliary Fuse Block, Hella Driving + Fog Lights, Backup Lights
    That was what I was leaning toward, a tee fitting on each side of the heater core with a ball valve on the side going to the bed on each. Anybody know where the two hoses pass though the firewall?
     
  7. Apr 2, 2012 at 5:38 PM
    #7
    Rich91710

    Rich91710 Well-Known Member

    Joined:
    Feb 23, 2012
    Member:
    #73470
    Messages:
    16,404
    Gender:
    Male
    First Name:
    Rich
    Los Angeles
    Vehicle:
    08 Base
    Satoshi with FJ badge, factory cruise, factory intermittent wipers, Redline Tuning hood-lift struts, Hellwig Swaybar, Rosen DVD-Nav
    Ya, I'd tap in on the exit side of the stock heater core.
    A bypass would be smart, but I would recommend leaving it open unless you have a problem or you could have corrosion issues from lack of flow.
    The Suburbans with rear heat simply "tee" off and run the rear heater core in parallel with the front core.
    They run steel lines to the bottom of the cab, then switch to rubber for the run along the frame and up into the rear heater core.

    Bleeding air from the system is going to be a B*I*T*C*H if you don't include a purge valve at the highest point in the added system. Even if the rear core is lower than the highest point in the engine, flushing the air in the rear DOWN and out the exit hose is a major hassle.
    Standard bleed procedure for a '95 Suburban is fill it, run it, fill it, run it, park it on a steep hill, and repeat.
     
  8. Apr 2, 2012 at 5:44 PM
    #8
    EntradaTaco

    EntradaTaco [OP] Member

    Joined:
    Feb 23, 2012
    Member:
    #73437
    Messages:
    9
    Gender:
    Male
    First Name:
    Brandon
    Utah
    Vehicle:
    04 SR5 TRD
    Grey Wire, ABS Switched, DRL Switched, Auxiliary Fuse Block, Hella Driving + Fog Lights, Backup Lights
    Good point with the purge valve, hadn't even crossed my mind! Do you know if the Suburbans use a buster pump to circulate it all the way to the back? Or maybe just a big-ass water pump...
     
  9. Apr 2, 2012 at 6:50 PM
    #9
    Rich91710

    Rich91710 Well-Known Member

    Joined:
    Feb 23, 2012
    Member:
    #73470
    Messages:
    16,404
    Gender:
    Male
    First Name:
    Rich
    Los Angeles
    Vehicle:
    08 Base
    Satoshi with FJ badge, factory cruise, factory intermittent wipers, Redline Tuning hood-lift struts, Hellwig Swaybar, Rosen DVD-Nav
    Just five point seven or more gas-guzzling litres :D

    Seriously though, no... it was simply tapped into the front heater core circuit.
    Basically the same thing for the rear AC... the compressor and condensor are the same, they just used different hoses that split off to the rear.
    The rear evaporator had a thermal expansion valve to control the flow of R134, so when the rear fan was not on, the valve would "freeze" and shut flow off. Turning the rear fan on warmed the valve and allowed it to open, allowing R134 to flow until the valve froze up again.
    Very primitive system and not very efficient, but it worked.
    Rear seat had a separate temp control so if the people in the back seat got cold they could open the heater core diverter door and warm the air a bit (heater core was after the evaporator so the expansion valve still closed when it got cold).
     
  10. Apr 2, 2012 at 6:58 PM
    #10
    EntradaTaco

    EntradaTaco [OP] Member

    Joined:
    Feb 23, 2012
    Member:
    #73437
    Messages:
    9
    Gender:
    Male
    First Name:
    Brandon
    Utah
    Vehicle:
    04 SR5 TRD
    Grey Wire, ABS Switched, DRL Switched, Auxiliary Fuse Block, Hella Driving + Fog Lights, Backup Lights
    That is primitive... also simple, and more importantly, hard to screw up. I'm yet to figure out the inner diameter of the line running in and out of the heater core? Seems like it has an outer diameter of 3/4 (rough estimate).
     
  11. Apr 2, 2012 at 7:09 PM
    #11
    hulkit

    hulkit Well-Known Member

    Joined:
    Nov 20, 2010
    Member:
    #46490
    Messages:
    73
    Gender:
    Male
    sacramento ca
    Vehicle:
    2000 tacoma 2.4l automatic
    pleae please please lots of pictures all these major mods are of much interest to me
     
  12. Apr 2, 2012 at 7:11 PM
    #12
    EntradaTaco

    EntradaTaco [OP] Member

    Joined:
    Feb 23, 2012
    Member:
    #73437
    Messages:
    9
    Gender:
    Male
    First Name:
    Brandon
    Utah
    Vehicle:
    04 SR5 TRD
    Grey Wire, ABS Switched, DRL Switched, Auxiliary Fuse Block, Hella Driving + Fog Lights, Backup Lights
    I'll follow up with pics as I get 'er done
     
  13. Apr 2, 2012 at 7:25 PM
    #13
    Rich91710

    Rich91710 Well-Known Member

    Joined:
    Feb 23, 2012
    Member:
    #73470
    Messages:
    16,404
    Gender:
    Male
    First Name:
    Rich
    Los Angeles
    Vehicle:
    08 Base
    Satoshi with FJ badge, factory cruise, factory intermittent wipers, Redline Tuning hood-lift struts, Hellwig Swaybar, Rosen DVD-Nav
    5/8 return and 3/4 supply are typical for Chevy. I can't imagine Toyota running 1/2", but I don't know, and my Taco is an '08 so a measurement may not do you any good.
     
  14. Apr 2, 2012 at 7:27 PM
    #14
    EntradaTaco

    EntradaTaco [OP] Member

    Joined:
    Feb 23, 2012
    Member:
    #73437
    Messages:
    9
    Gender:
    Male
    First Name:
    Brandon
    Utah
    Vehicle:
    04 SR5 TRD
    Grey Wire, ABS Switched, DRL Switched, Auxiliary Fuse Block, Hella Driving + Fog Lights, Backup Lights
    Is it normal to have a different size supply and return?
     
  15. Apr 2, 2012 at 7:31 PM
    #15
    Rich91710

    Rich91710 Well-Known Member

    Joined:
    Feb 23, 2012
    Member:
    #73470
    Messages:
    16,404
    Gender:
    Male
    First Name:
    Rich
    Los Angeles
    Vehicle:
    08 Base
    Satoshi with FJ badge, factory cruise, factory intermittent wipers, Redline Tuning hood-lift struts, Hellwig Swaybar, Rosen DVD-Nav
    It's not uncommon.

    And it makes for some fun times when you have a 5/8 and 3/4 on the stock core and an aftermarket unit that's 1/2 on both.
     
To Top