Close



Results 1 to 9 of 9
  1. #1

    Default Hot Idle Compensator Valve

    I have a 1985 Ford Mustang 5.0L 4V. I am looking for a replacement hot idle compensator valve AND PIPE/TUBE that connects to the PCV valve. I can't find any in the local wrecking yards or on Ebay. Does anyone have a part number for this?

    Here is a picture of what I am looking for. Notice the pipe/tube is part of the HICV:

    http://st.hotrod.com/uploads/sites/2.../178059257.jpg

  2. #2
    FEP Senior Member
    Join Date
    Dec 2016
    Location
    Grand Rapids, MI
    Posts
    721

    Default

    This looks awfully similar. I'm not sure how that bracket attaches. What search words are you using? Try fast idle solenoid or idle stop solenoid. THere are a couple others similar to this on ebay also listed as idle stop solenoids.

    http://www.ebay.ca/itm/BWD-ECS102-Ca...1ZUlce&vxp=mtr
    '89 XR-7 5 Speed
    '95 SC 5 Speed
    '91 Crown Vic P72 351W
    '97 Thunderbird
    '85 Ford LTD Squire

  3. #3

    Default

    Thanks, but that is not what I am referring to.

    I am looking for the steel line/tube that connects from under the front and middle of the carburetor to the PCV valve, with the hot idle compensator in it.

  4. #4
    FEP Super Member xctasy's Avatar
    Join Date
    Jun 2012
    Location
    Dunedin 9011, New Zealand, South Pacific
    Posts
    3,961

    Default






    This is used on a good deal of Fords from 1963 onwards.

    1984-1985 4180C 4-BBL Holley



    1978-1980 1946 Holley (not 1981-1983 1946C, but it still has the plate for it)



    1977-1985 2150 Motorcraft 2bbl



    1969-1982 Holley Weber 5200-5210



    1968-1971 4300 Autolite Speadbore



    1965-1968 4100 Autolite




    Set-up procedure

    http://www.network54.com/Forum/88781...pensator+Valve

    The engine needs to be like goldilocks' porridge. Not to cold, not too hot, but just right. The shop manual for my 1963 Thunderbird says the purpose of the hot idle compensator valve is to allow more air into the idle mixture to help control an over-rich mixture when the entering air is very warm. The manual states that the over-rich mixture would result from the fact that the warmer air atomizes the fuel better, thus making less fuel necessary. It is kind of a negative choke, it sounds like. It continues to lean the fuel mixture at idle as the air warms, even after the choke valve is completely open. I suppose that, wherever along the continuum (from full choke to full negative choke) you set the idle, it will be a compromise. The car will be set to idle optimally when the engine is idling at that point on the continuum. But at other points on the continuum, the engine will probably be idle less than optimally. The engineers, by tial and error or by design, presumably determined that the best compromise, overall was achieved by setting the idle to be most efficient when the choke valve was fully open but the hot idle compensator valve was still closed. I don't know what temperature the hot idle compensator valve opens at. But one consideration the engineers may have had in mind is that it may be difficult or time consuming to get a healthy engine idling in a chilly mechanic's shop in the winter with the hood open and the air filter off to run hot enough that the valve will open. Therefore, they designed it so that the best result would be achieved if the idle was set when the hot idle compensator valve was closed

  5. #5
    FEP Super Member xctasy's Avatar
    Join Date
    Jun 2012
    Location
    Dunedin 9011, New Zealand, South Pacific
    Posts
    3,961

    Default

    Hmmm. Hot Idle Compensator Valve1983 is identified by List 50223. Both 1984 and 1985 are List 50265

    only near match is the 67-68-69 Mercury Cougar one for 235 bux.







    Mikes Carbs

    The Hot Idle Compensator is used on some carburetors to offset enriching effects caused by percolation during hot operation. Generally used on vehicles with air conditioning. When the engine is running hot and then stopped, the fuel can boil or percolate and vaporize causing a rich condition at idle.


    On all the other carbs, the compensator is mounted on top of the venturi, or behind the float bowl and at a extreme hot temperatures, the bi-metal thermostat bends and opens a passage that leads from the venturi to below the throttle valves. This adds just enough air to the fuel mixture to lean out the fuel giving you a smoother idle.

    Be sure the compensator is closed when adjusting the idle mixture, otherwise you may be getting too much air introduced.
    https://secure.cougarpartscatalog.co...mpensator.html

    This is an original NOS hot idle compensator for Mercury Cougar or Ford Mustang models with V-8 engine and factory A/C. It is installed in the middle of the hose that connects the PCV valve to the rear of the carburetor spacer. It opens when it reaches a certain temperature which makes the engine run faster when at idle and the A/C is on thereby making the engine run more efficiently. This is an original Ford part that came on air conditioned models from the factory. It was manufactured by Carter and has the original "CARbureT ER" logo stamped on the underside of the top arm. This part is mostly brass and is in great shape. It has never been installed. If yours is missing or defective this is an excellent replacement. It is also correct for Fairlane, Galaxie, Torino, and other Ford & Mercury applications. Limited quantity and a very rare and hard to find part in NOS form!

    *NOTE* This answer was given at www.ask.com; When the under-hood temps get very hot, the fuel has a tendency to want to boil in the carburetor. When it boils, it percolates with bubbles like a coffee maker and will push fuel out of the carburetor over into the engine, making it idle rich and run rough. The idle compensator opens up when it gets hot, letting air into the vacuum line, basically a vacuum leak. This makes the engine idle faster, which turns the fan faster, which helps cool down the under-hood temperature and basically makes it idle better on a very hot day.
    From VMF; "When the ambient under hood temp increases to a certain point the bi-metallic strip on the hot idle compensator opens a rubber needle - brass seat metered orifice, causing what is essentially a vacuum leak of a predetermined amount into the intake system. This extra air will in turn cause the idle speed to increase, moving more air through the radiator and water through the cooling system due to increased fan and water pump speed the result being the motor will cool down to the point where the ambient under-hood temp is lower, and the valve closes and the vacuum leak will stop, returning the engine to a normal idle speed.This cycle repeats itself over and over. Obviously this will only help during periods of engine idle. Remember, this was engineered in the early sixties and in theory is workable. What normally happened is that IF the little rubber needle valve did lift from the brass seat and cause the idle to increase, it sometimes would not seat properly when cooler, and caused an erratic idle. Most were tossed in the garbage back in the day. In the real world, this little device probably caused more problems than it solved! It had a somewhat short life, was kind of a band-aid fix, and was replaced with a bigger and better cooling system as more and more Ford products were sold with factory A/C."
    A partial other match is the GM Van 250 in line six




    Also used in 61 and 62 Holley carbed A/C Galaxies, about US $49.00













    https://www.ebay.com/itm/GM-Rocheste...lZ8gYL&vxp=mtr

  6. #6

    Default

    I have the screw-in hot idle compensator valve itself, I just need the steel tube.

    On these Mustangs, the hot idle compensator valve holder is welded to the steel tube.

  7. #7
    FEP Senior Member
    Join Date
    Dec 2016
    Location
    Grand Rapids, MI
    Posts
    721

    Default

    Quote Originally Posted by RickFury View Post
    Thanks, but that is not what I am referring to.
    My bad. I saw the fast idle solenoid and focused on that for some reason. Good luck with your search.
    '89 XR-7 5 Speed
    '95 SC 5 Speed
    '91 Crown Vic P72 351W
    '97 Thunderbird
    '85 Ford LTD Squire

  8. #8
    FEP Member Mgino757's Avatar
    Join Date
    Jan 2011
    Location
    Virginia Beach, VA
    Posts
    489

    Default

    I too would like to know where one can be obtained. Mine is missing, PCV is hooked up with a normal rubber hose.
    1985 Mustang GT conv. modified 4180C, Weiand Street Warrior intake, equal length headers, true dual exhaust, 3.55:1 8.8'' rear end, 2003 V6 T5, Ford Racing 10.5" clutch.

    1998 Mustang GT auto. PI swapped. Daily beater

  9. #9
    FEP Power Member 85stanggt's Avatar
    Join Date
    Nov 2005
    Location
    Ft. Lauderdale, FL
    Posts
    2,285

    Default

    Does anyone know what temperature it is supposed to open at? I would like to make sure mine works. I "adjusted" it at some point years ago
    1985 Mustang GT Convertible
    Stock and original @ 213k, except for dynomax ultraflos.

Posting Permissions

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