FYI FORD - MustangSteve's Ford Mustang Forum
The Internet's Most Knowledgeable Classic Mustang Information
IF YOU HAVE A QUESTION ABOUT CLASSIC FORD MUSTANGS, YOU HAVE COME TO THE RIGHT PLACE!
MustangSteve has over 30 years of Mustang experience, having owned 30 of them and restored several others. With the help of other Mustangers, this site is dedicated to helping anyone wanting to restore or modify their Mustang.... THERE ARE NO DUMB QUESTIONS!!!!!
Visit MustangSteve's web site to view some of my work and find details for:
FYIFORD Contributors' PICTURES - Power Brake Retrofit Kits for 65-66 Stangs - Classic Mustang FAQ's by MustangSteve - How to wire in a Duraspark Ignition - Mustang Ride Height Pictures and Descriptions - Steel Bushings to fit Granada Spindles to Mustang Tie Rods - Visit my EBAY store MustangSteve Performance - How to Install Granada Disc Brakes MustangSteve's Disc Brake Swap Page - FYIFORD Acronyms for guide to all the acronyms used on this page - FYIFORD Important information and upcoming events

You are not logged in. Would you like to login or register?

  • Index
  •  » FYI Ford, Classic Mustang Tech Discussion
  •  » vacuum leak through choke heat tube?

    • 1 of 1

       

    4/30/2013 7:23 AM  #1

    LondonSteve
    FYI Addict

    Offline

    From: London, Ontario, Canada
    Registered: 4/01/2013
    Posts: 136

    vacuum leak through choke heat tube?

    I do not have the choke heat tube connected to the manifold. I just noticed there is a slight air draw on the open fitting at the carb.

    Does this have any effect on performance of the carb ( vacuum leak ), and should be plugged, or does it matter?

    Can't tell if it is a vacuum draw or just a fresh ( warm ) air pull into the choke only.

    Thanks

     

    4/30/2013 7:33 AM  #2

    Hornman
    Senior 24-7 FYI Addict

    Offline

    From: Mansfield, Texas
    Registered: 4/01/2013
    Posts: 1,568

    Re: vacuum leak through choke heat tube?

    If you are talking about the tube into the top airhorn of the carb, you should plug it because it is allowing unfiltered air into your carb.

     

    4/30/2013 8:09 AM  #3

    hmartin025
    I FYI 24-7

    Offline

    Registered: 4/01/2013
    Posts: 365

    Re: vacuum leak through choke heat tube?

    Steve, thats perfectly normal. Thats how air reaches the bi-metalic spring that opens your choke.
    Howard

     

    4/30/2013 11:31 AM  #4

    MS
    Forum Originator

    Offline

    From: Canyon Lake, Texas
    Registered: 1/24/2013
    Posts: 11,729

    Re: vacuum leak through choke heat tube?

    Like hmartin said, the vacuum allows air to get to the bimetallic spring in the choke.  It is a very tiny vacuum leak, but apparently causes no grief.

    I think hornman was thinking of the 1/4" tube that some carbs have that points downward from the flat part of the carb airhorn.  That one should be plugged.  Not all carbs have that one.  Mostly OEM Holleys and emission type carbs.

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

    5/01/2013 5:30 PM  #5

    Hornman
    Senior 24-7 FYI Addict

    Offline

    From: Mansfield, Texas
    Registered: 4/01/2013
    Posts: 1,568

    Re: vacuum leak through choke heat tube?

    The 1/4" port on the right side of the air horn was used as a "filtered air" supply and piped down to the sheet metal choke stove on the manifold, then the choke heat tube routed the warmed air to the choke. This supply tube wasn't used on many models, but was used on some. The big parts stores still sell the tubing kits.  These kits work well with headers.

    What makes the filtered air supply funny is that the choke actuation rod penetrates the air horn without a seal, allowing in unfiltered air.

     

     

    1 of 1

  • Index
  •  » FYI Ford, Classic Mustang Tech Discussion
  •  »  vacuum leak through choke heat tube?

    • Board footera


    REMEMBER!!! When posting a question about your Mustang or other Ford on this forum, BE SURE to tell us what it is, what year, engine, etc so we have enough information to go on.