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How Do I Fix & Preserve Carb Vac To Maintain CRX HF MPG?

Discussion in 'Civic and CRX - EW' started by Ascendedmind, Mar 18, 2016.

  1. Ascendedmind

    Ascendedmind New Member

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    Hi, I just bought a 1985 Honda CRX HF 1.5 with 3 barrel carburetor. Everything is original & stock. Only has approx. 125,000 miles. I bought as an alternative to a hybrid. I really appreciate this car & working on restoring everything.


    I realize this is a Honda CRX Performance forum, however I bought this version for High Fuel Economy & not for performance. Fans of the HF say don't devac if you want to maintain or keep the same MPG rating. In other words keep it stock.


    Presently the carb or insulator base plate gasket has a noticeable vacuum leak verified with carb cleaner.


    When started cold it idles approx. at 2350 RPM then when it warms up kicks down to about 1350 RPM.

    Now at what speed should the motor be idling at from a cold start & what idle speed when warmed?


    Under hood says 650-750 RPM for HF


    Do you recommend I have a professional smoke test performed on the engine to check for any & all vacuum leaks?


    Note: It was recommended by Permatex & others to use Permatex Permashield Fuel Resistant gasket dressing (aka Hylomar Universal Blue( which is Non-Hardening & Non-setting as a solution for the carburetor insulator or base plate gasket. If gasket is salvageable then use together with the Permashield.


    Please don't recommend devac or replacing with Weber as I'm not interested in performance. I do have a brand new Honda Service Manual for my 1985 Honda Civic CRX ( HF model). But I'm not mechanically inclined, but can read & follow directions.


    Any suggestions for finding a capable or good Honda mechanic in the Pacific NorthWest? I live in the Seattle-Tacoma area in Puyallup by the State Fair.


    However, I may be forced to learn this.


    Any special tools I definitely need to get? I bought a carburetor rebuild kit, float kit & purchased the last Needle & Valve from Honda.
     
  2. dilbeckskate

    dilbeckskate infamous

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    Theres no fix but a full rebuild kit that they dont make anymore , sorry
     
  3. Ascendedmind

    Ascendedmind New Member

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    What typically fails in the vacuum system? Just mainly the carb base plate gasket for vacuum leaks?
    What other things typically fail, which I need to test, before replacing?
     
  4. dilbeckskate

    dilbeckskate infamous

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  5. Ascendedmind

    Ascendedmind New Member

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    Thanks, now do the diaphragm gaskets typically come with the commonly available carb rebuild gasket set?
    If not, was there a specific diaphragm gasket set previously available from Honda?
     
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