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  •  » A/C question

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    8/25/2013 6:48 AM  #1

    Rudi
    Senior 24-7 FYI Addict

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    From: Stuck in the 50's Welland Ca
    Registered: 4/01/2013
    Posts: 3,789

    A/C question

    I have a Classic Auto Air sysytem in my 68.
    At idle it blows cold, at speed it is 10-15 degrees warmer. Any ideas why?

    Good work ain't cheap, Cheap work ain't good!   Simple Man
     

    8/25/2013 7:46 AM  #2

    jerseyjoe
    I FYI 24-7

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    Registered: 4/01/2013
    Posts: 789

    Re: A/C question

    Rudi wrote:

    I have a Classic Auto Air sysytem in my 68.
    At idle it blows cold, at speed it is 10-15 degrees warmer. Any ideas why?

     
    Rudi be sure all the bubbles are gone from site glass, may be a little low on freon...heater door may be opening slightly...loose belt....jj

    "Never put a question mark where God put a period "  Richard Petty
     

    8/25/2013 7:22 PM  #3

    BillyC
    I FYI 24-7

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    From: Chesapeake, Va.
    Registered: 4/02/2013
    Posts: 965

    Re: A/C question

    Rudi wrote:

    I have a Classic Auto Air sysytem in my 68.
    At idle it blows cold, at speed it is 10-15 degrees warmer. Any ideas why?

     Sounds like you're getting hot air infiltrating from some where. If its blowing cold at idle the charge is probably ok.

    "anyone that stops learning is old, whether at twenty or eighty"Henry Ford
     

    8/25/2013 8:42 PM  #4

    Rudi
    Senior 24-7 FYI Addict

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    From: Stuck in the 50's Welland Ca
    Registered: 4/01/2013
    Posts: 3,789

    Re: A/C question

    The blend doors are all cable operated and no outside air is used, it is a closed loop system. It heats or cools only the air inside the vehicle.
    The heat shut off cable closes a valve on the heater hose to keep hot coolant out of the heater core when in the cooling mode. 
    All outside air vents have been sealed shut.
      I'm stumped on this one!

    Good work ain't cheap, Cheap work ain't good!   Simple Man
       •Thread Starter
     

    8/25/2013 8:54 PM  #5

    Raymond_B
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    From: Fort Worth, TX
    Registered: 4/01/2013
    Posts: 1,128

    Re: A/C question

    Rudi wrote:

    The blend doors are all cable operated and no outside air is used, it is a closed loop system. It heats or cools only the air inside the vehicle.
    The heat shut off cable closes a valve on the heater hose to keep hot coolant out of the heater core when in the cooling mode.
    All outside air vents have been sealed shut.
    I'm stumped on this one!

    Belt slippage? Or I remember a long time ago when working at an auto parts store we had to set the compressor clutch gap when selling new/rebuilt units. That would cause it to slip as well at higher RPMs.

    Last edited by Raymond_B (8/25/2013 8:55 PM)

     

    8/25/2013 9:09 PM  #6

    MS
    Forum Originator

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    From: Canyon Lake, Texas
    Registered: 1/24/2013
    Posts: 11,744

    Re: A/C question

    I don't know if this has anything to do with yours, but on my 66, the AC was ice cold driving around in town but the car got hotter on the highway.  I figure it was due to the leakage around the windows, etc sucking the cold air out at high speed.

    Is yours possibly freezing up at speed?

    Money you enjoy wasting is NOT wasted money... unless your wife finds out.
     

    8/26/2013 5:13 AM  #7

    ChrisH IA
    FYI FORD Member

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    From: Des Moines, Iowa
    Registered: 4/01/2013
    Posts: 43

    Re: A/C question

    As Raymond B said, clutch slippage was my problem, too; it wasn't the clutch as such, but the carbon brush that wouldn't make good contact at higher engine speeds. Just enough oil from the compressor to gum up the brush holder-spraying with brake cleaner is a short term cure (Don't spray while engine is running)

     

     

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