Airhead Carb and tank cleaning question

Discussion in 'Airheads' started by wanderind, Oct 9, 2010.

  1. wanderind

    wanderind Been here awhile

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    For a bike that has been sitting for years and needs both tank and carbs cleaned, how difficult and expensive is the job if I am doing it myself? I am a noob on airheads and any info regarding the procedure and links to good stuff will be appreciated. If the tank needs cleaning, does it mean the fuel pump, filter and lines may also need replacement?
    #1
  2. Hawk Medicine

    Hawk Medicine Coyote's Brother

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    Use Google and do a search of the "Olds Cool" archives.

    This subject has been the subject of literally dozens of threads. :norton
    #2
  3. fishkens

    fishkens Long timer

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    Year and model would help a bit.

    How difficult? That depends a lot on you. I'm no genius but I've rebuilt my carbs multiple times w/out fatal errors.

    Parts and a good manual can be purchased here:
    http://www.bingcarburetor.com/
    http://www.advrider.com/forums/showthread.php?t=602188

    Tips
    http://w6rec.com/duane/bmw/tuning.htm
    http://bmwmotorcycletech.info/bingcv.htm - Read this with caution and if it starts to scare you off take a break - it's not really that complicated. Eventually, you'll want to read most of what he writes but pace yourself - I think I'm going on 10 years now. Unfortunately, it seems that it was written before images could be easily transmitted on the intertoobes.
    http://www.advrider.com/forums/showthread.php?t=355137

    Zillions of Threads on advrider.com

    Enter this in google:
    => rebuilding airhead carbs site:advrider.com
    And get this:
    http://www.google.com/search?hl=en&source=hp&q=rebuilding+airhead+carbs+site%3Aadvrider.com&btnG=Google+Search&aq=f&aqi=&aql=&oq=&gs_rfai=CfTwrrr2wTPfmEoWaoASn5LjaCwAAAKoEBU_Qeomp

    As for the airhead fuel pump, you'll be pleasantly surprised - it's entirely maintenance free and guaranteed to last a lifetime.

    Enjoy.
    #3
  4. pjcr12

    pjcr12 Stercus accidit

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    801
    It's not too difficult a job, it's more a question of methodically going through it all. The tanks can suffer from pin-hole leaks around the lower seams, but if you seal it with petseal (or equivalent) after cleaning out any rust flakes or accumulated grot in the tank, you should be ok. The petcocks have gauze filters inside them which can clog, and the fuel lines are best replaced if they've been on the bike for a long time. As for the carbs themselves, take the tops off to check that the diaphragms aren't split or perished. The float bowls will come off by releasing the holding clips, which will give you access to the floats, the float needles and the jets. There may well be a lot of gunge in this area, again if the bike has been stood for a long time. Work on each carb separately, on the bench, and use your Haynes or Clymer book to identify parts as you go, and use a can of carb cleaner. One word of caution; I've found that the brass main jet holder is easily rounded, so be careful. I'm sure other ADV'ers will offer advice, but just take it easy, go slow and don't drop anything!
    #4
  5. wanderind

    wanderind Been here awhile

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    Thanks a ton!....you guys are great. I will go through all this and chip back in if I have more Qs...:clap BTW The bike is a 87 R80
    #5
  6. wanderind

    wanderind Been here awhile

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    How significantly different is carb cleaning vs carb rebuild?:eek1
    #6
  7. fishkens

    fishkens Long timer

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    In terms of results, about the same difference between washing a car and repainting it. If the wear parts are in great shape a cleaning is fine. If the wear parts are worn no amount of cleaning will put a shine on it.

    In terms of time? If you remove the carbs, clean 'em up real nice, reinstall them and find that the motor doesn't idle because all the wear parts are worthless you'll need to remove the carbs and rebuild 'em, i.e. a cleaning and a rebuild may take twice the time as a rebuild alone.
    #7
  8. wanderind

    wanderind Been here awhile

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    Thanks Fishken...your reply implies that rebuild will take the same amount of time and effort except for the new additional parts and o-rings, right?
    #8
  9. fishkens

    fishkens Long timer

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    Replacing all the o-rings, enrichener gasket, diaphraghm and possibly the needle will definitely take a bit more time but it's probably necessary if they haven't been attended to in quite sime time.

    Have you started it? You could start by flushing the tank and carb bowls, putting in fresh gas and running it to see what you've got.

    Depending on your goals you'll probably want to assess the entire bike and put together a plan to bring it to the condition you want.

    Here's an example of a methodical approach to the process:

    http://www.advrider.com/forums/showthread.php?t=431153
    #9
  10. wanderind

    wanderind Been here awhile

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    havent started it...but thanks for the link and info..will get on it soon and document the thing:1drink
    #10
  11. fishkens

    fishkens Long timer

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    #11
  12. wanderind

    wanderind Been here awhile

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    #12
  13. rufusswan

    rufusswan Been here awhile

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    Rebuild means replace replaceable compnents. Other than grung, gaskets, O-rings, diaphrams, the needle and its jet must be replaced as a pair and should be about it unless .... I had to replace the washer/shims on the main. All else might clean up. Dismantle and clean the petcocks, replace the gas lines, clean out the tank.

    Ten minutes of research on the inter-stupid will result in divergent tank cleaning methodologies and will result in an 'oil thread' headache of a severe nature. It would be best to take a pic of the tank bottom at the fill opening and then scratch that area to determine how rusty it might be. I did 4 tanks this year with different methods depending on "what" I was attempting to clean out of the tank.
    #13