Help my Mav only runs on carb. cleaner

Discussion in 'Technical' started by royle, Apr 29, 2009.

  1. royle

    royle New Member

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    The fuel filter is on correct and the carb is getting fuel. I will try tunning the carb at 1 1/2 turns out instead of 2 1/2 like I have been and see if that does not fixthe issue. I would rather start cheap and work my way up;)
     
  2. PaulS

    PaulS Member extrordiare

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    Bigdmadgrabber is probably correct. After sitting for a year your carb probably needs to be rebuilt. The gaskets shrink, passages and bleeds get clogged when the fuel in the carb evaporates - leaving the gum behind.
    When you buy a kit be sure it is a genuine Holley kit. The aftermarket kits are sometimes problematic.
     
  3. baddad457

    baddad457 Member

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    When was the last time you changed the points? If you're still running them, that's the first thing that needs to go on the way to getting it running again. Ditch the points NOW.
     
  4. dmhines

    dmhines Dixie Maverick Boy

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    Carb cleaner generally stalls your car ... not make it run better ... :)
     
  5. Old Guy

    Old Guy Member

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    Biggest culprit of your description, is bad gas. Moisture in the fuel will cause the backfiring also, as the atomization in the cyl. becomes hot and steamy. Hot spots on any carbon build up, will fire what vapor's are available, at any given time before piston get's to preset ignition timing, causing pre ignition or lean condition. If you can clean out the carb and drain the old gas from the tank, may be the culprit. Just for info, carb cleaner will run an engine just fine, unless you over spray to the point of flooding the intake with it. Mainly just use it for starting only, don't know if using lot's of it will damage internal part's or not. My guess is yes, especially washing down cyl. wall's. Good luck with finding the problem.
     
  6. brainsboy

    brainsboy Member

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    I dont know about the old gas causing that. I have had some cars run on some pretty crappy old gas before. I drove bettsy home (a 72 comet) 125 miles on 1 year old gas. Smelled like rotten gas until I filled it up with new gas.
     
  7. jncastell

    jncastell Member

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    In the old days was always told carb cleaner would eat your gaskets & enginge starting fluid would fry parts of your engine when used to often.
     
  8. brainsboy

    brainsboy Member

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    hehehe never heard that one, I was always told to stick moth balls in the gas tank. Never really noticed it working or making the gas better but it did keep the bugs away.
     
  9. cdeal28078

    cdeal28078 Member

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    My money is on the dried up gas in the carb. I does not take very long for the gas to evaporate leaving a nasty white ash looking gunk all over the inside of the bowls and metering blocks making it impossible for the carb to meter the fuel right.
    I have had good luck with the AED kits as well but the more expensive Holley kits usually have more parts in them like the elusive throttle shaft bushing pieces.
    clint
     
  10. royle

    royle New Member

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    Update

    Today I got the car to idle on its own. The car was almost out of gas so i put in 5 gallons, before I thought the car was half full of gas. After messing with the lean/rich screws on the carb I was able to get the old mav to idle on its own with two turns out from all the way in. I only ran the car for a minute because it dawned on me that the oil still has water in it:naughty:. The engine sounded ok in the bay but the exhaust sounded like a steam train or the sound you make when you roll your R's. When I try to rev the engine the car stalls and dies after idle. I still am running points on the car. Thanks for the help so far, I hope to have the ol beast up and running before it gets to hot out.
     
    Last edited: Apr 30, 2009
  11. Old Guy

    Old Guy Member

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    Yep, the original mothball's had ether in them and worked quite well in the old Harley police bike's. I used to run Cox model airplane fuel in my flat head Desoto 6cyl, 33 Chrysler coupe, stock car. A pint to 5gal. of gas, the can said 75% nitro. Don't think they use that anymore either, in it. Tried 2 cans one time and really got a boost out of it. Thought about 3 one night but did not want to blow the head off and create a dangerous situation. That was the only non Ford race car, I ever owned.
     
  12. baddad457

    baddad457 Member

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    :huh: I thought mothballs had benzene :hmmm:
     

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