Audizine - An Automotive Enthusiast Community

Results 1 to 13 of 13
  1. #1
    Senior Member Two Rings B. Rock's Avatar
    Join Date
    Jul 27 2008
    AZ Member #
    31331
    My Garage
    91 CQ
    Location
    Denver, CO

    Coolant Crossover Pipe

    Guest-only advertisement. Register or Log In now!
    Per the recommendation of most on here, I snagged the crossover pipe (#4) while I have the blower off for PCV replacement. However, #22 looks like it'd be prone to heat cracking as well but I don't see anyone replacing it. It's only $35 so I'm probably going to do it anyway, anyone else BTDT?
    Cooling System Snip.PNG
    13 SHO
    09 A6 Avant 3.0t
    96 FZJ80
    95 UrS6 (RS2'd)
    82 TDI Adventurewagen

  2. #2
    Senior Member Three Rings
    Join Date
    May 23 2016
    AZ Member #
    373689
    Location
    Edmond, OK

    That's a good point. I've yet to see someone mention replacing that pipe. I think that #22 runs sandwiched under the IM/ over the PCV box, correct? I'd think that it sees more heat than even the x-over pipe... and yet no one replaces it?
    07 A6 3.2- Out & In- Morimoto 5500k & Nokya 2500k, DeAutoLED Reverse, LP, & Footwells, Ziza Full Interior, 10" lo-pro Pioneer, Audi Aluminum Pedals
    Drivetrain & Suspension- Stoptech X-Drilled & Sport Pads, ST X-Coilovers, Hacked Airbox with aFe, Resonator Delete

    "What is best in life? -Kill your enemies. See them driven before you. And hear the lamentation of their women" Conan the Barbarian

  3. #3
    Senior Member Two Rings B. Rock's Avatar
    Join Date
    Jul 27 2008
    AZ Member #
    31331
    My Garage
    91 CQ
    Location
    Denver, CO

    Bingo. I was scratching my head when I took the blower off and saw it sitting there, right in the middle of the V, but didn't see any mention of failure or replacement.
    13 SHO
    09 A6 Avant 3.0t
    96 FZJ80
    95 UrS6 (RS2'd)
    82 TDI Adventurewagen

  4. #4
    Established Member Two Rings juniorcruzer's Avatar
    Join Date
    Sep 28 2014
    AZ Member #
    285681
    My Garage
    2007 Suburban
    Location
    Center City Minnesota

    I had to replace that exact pipe, 22, when I replaced the PCV...that is where my invisible coolant loss was coming from. Has to come out to replace the PCV, so for the price, would absolutely recommend replacing.

    Jon
    2010 S4 3.0T, chipwerks stage I
    2010 A6 3.0T, APR Stage 2+, Roc Euro Intake, VMR V710 18x9.5 HyperSilver, 30% tint, A3 clear marker lights, LED Reverse lights, RS6 Grill

  5. #5
    Senior Member Three Rings
    Join Date
    May 23 2016
    AZ Member #
    373689
    Location
    Edmond, OK

    Very interesting Jon, thanks for your feedback.

    This is a tube that feeds (or brings back) coolant from the heater core behind the firewall, is it not?


    This may be looking further into it than merited, but...
    I wonder since it doesn't get used year round, it doesn't see the wear and tear that other cooling system components see. I've yet to hear of anyone here replacing a heater system coolant-component (besides Jon above mentioning it was the culprit of his invisible coolant loss). If this observation is true, I wonder then... how much of our cooling system's wear and tear is caused by plastic becoming brittle due to heat cycles, versus the combination of heat cycles and cooling system becoming acidic over time? For example, we far more often replace items that are under constant flow (x-over pipe, t-stat, for example), contrasted by how seldom we hear of replacing heater system components that do not get used as often. Heater components are still under the same pressure as the rest of the cooling system, but only see coolant FLOW when the heater is on.
    // end rambling lol
    07 A6 3.2- Out & In- Morimoto 5500k & Nokya 2500k, DeAutoLED Reverse, LP, & Footwells, Ziza Full Interior, 10" lo-pro Pioneer, Audi Aluminum Pedals
    Drivetrain & Suspension- Stoptech X-Drilled & Sport Pads, ST X-Coilovers, Hacked Airbox with aFe, Resonator Delete

    "What is best in life? -Kill your enemies. See them driven before you. And hear the lamentation of their women" Conan the Barbarian

  6. #6
    Veteran Member Three Rings cal3thousand's Avatar
    Join Date
    Feb 19 2013
    AZ Member #
    109847
    My Garage
    1994 Volvo 850 Turbo
    Location
    Los Angeles

    FWIW, I inspected that tube and found it to be in good condition. So I just replaced the seal at the end.
    Danton Black: 2009 Audi C6.5 A6 Sedan (Quattro, 3.0T, Prestige)
    I miss my Avant, longing for a 2011 3.0T
    Dead:
    Griselda, aka Grizzy: 2007 Audi C6 A6 Avant (Quattro, S-Line)

    Just some small cosmetic mods while getting to Stage 0

  7. #7
    Active Member Two Rings
    Join Date
    Dec 15 2017
    AZ Member #
    411183
    My Garage
    2005 S4 6MT Quattro (2.7TT Swap Project)
    Location
    Northern Colorado

    FWIW I have replaced a few of them for leaking. It usually isnít just the seal but the end of the pipe eroding away. If your doing preventative replacement and have the blower off and replacing cooling system components, for the price and the effort with everything off already, I highly recommend.

  8. #8
    Active Member Two Rings
    Join Date
    Sep 04 2018
    AZ Member #
    426119
    Location
    South east

    When my blower comes off for the ported seapput I am doing PVC as well and I was planning on replacing the cross over and that pipe as well along with the thermostat. Just to cheap not to do it all while you are in there already.

  9. #9
    Active Member Two Rings
    Join Date
    Dec 15 2017
    AZ Member #
    411183
    My Garage
    2005 S4 6MT Quattro (2.7TT Swap Project)
    Location
    Northern Colorado

    I completely agree.

  10. #10
    Senior Member Two Rings B. Rock's Avatar
    Join Date
    Jul 27 2008
    AZ Member #
    31331
    My Garage
    91 CQ
    Location
    Denver, CO

    I now have the part in hand. Ended up with the same logic - I'm in there, and it's $30 now or pulling the blower again later.

    However, a question - how do you remove the clamp on the back end? It's 100% smooth all around, clearly a factory fitting, but there's nothing obvious to loosen up unlike the 1 time use clamps.
    13 SHO
    09 A6 Avant 3.0t
    96 FZJ80
    95 UrS6 (RS2'd)
    82 TDI Adventurewagen

  11. #11
    Veteran Member Four Rings SinCityA6's Avatar
    Join Date
    Jul 17 2011
    AZ Member #
    78357
    My Garage
    '07 Mustang GT Tungsten Grey/Black
    Location
    Sin City, USA

    Mine was replaced when I did the PCV service as well.


    Sent from my iPhone using Audizine
    '09 C6.5 A6
    M: 3.0t, GIAC/AWE Stg II+, Roc*Euro Intake
    I: Soul Black, CF Trim, LEDs, Paddles, C7 Shifter, Escort 9500i, Blackvue Dashcam
    E: Ibis White, 15% Tint, Smoked Corners, Tinted Tails, S4 Rockers, S6 Blades, RS6 Grill, OEM Splitters (F/R)
    S: H&R Springs/Sways, Koni FSDs, Adams Rotors, Akebono Pads, SS Brake Lines, Paint Matched Calipers, Niche Misano M116 Wheels

  12. #12
    Active Member Two Rings
    Join Date
    Dec 15 2017
    AZ Member #
    411183
    My Garage
    2005 S4 6MT Quattro (2.7TT Swap Project)
    Location
    Northern Colorado

    Unsure what clamp you are speaking of. The back comes off with a quick decoupled that you pull out a spring clip to be able to release. Then itís one bolt that holds it in place and the pulls straight back.

  13. #13
    Senior Member Two Rings B. Rock's Avatar
    Join Date
    Jul 27 2008
    AZ Member #
    31331
    My Garage
    91 CQ
    Location
    Denver, CO

    Yes, that's correct. It was dark when I was looking around back there and didn't see the quick connect. FWIW the crossover pipe broke in my hands upon removal but this one didn't. However the original did show signs of leakage at the o-ring where it went into the thermostat.

    Side note - just fired it up after a carbon clean, pcv, thermostat, water pump, both plastic coolant lines, both belts, fresh supercharger oil, and spark plugs. What a pain in the butt, hope it's worth it in the long run. I replaced the o-rings in each of the quick connect fittings with new just for my own sanity since some of those would be obnoxious to get to once everything was back together, and they were about $1-2 ea.
    13 SHO
    09 A6 Avant 3.0t
    96 FZJ80
    95 UrS6 (RS2'd)
    82 TDI Adventurewagen



Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  


    © 2001-2019 Audizine, Audizine.com, and Driverzines.com
    Audizine is an independently owned and operated automotive enthusiast community and news website.
    Audi and the Audi logo(s) are copyright/trademark Audi AG. Audizine is not endorsed by or affiliated with Audi AG.