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Thread: methanol back fires

  1. #1

    methanol back fires

    Can anybody give me tips on starting an engine on methanol without backfiring. Cold and hot. Seems like everytime it backfires it knocks a tooth off the fexplate or the starter. I have a 632 ci, 14to1 compression. Do I start it on gas everytime or not. Give it some gas before or after engauging the starter. Any info will help. Thanks, John

  2. #2
    Administrator RACING JUNKIE bjuice's Avatar
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    what are you running as your fuel delivery system..also is it a carb, injection etc....

    Brian
    Bjuice..

    "I'M YOUR HUCKLEBERRY ! "

  3. #3
    Senior Member MASTER BUILDER
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    The kickback problem usually comes with either a locked out distributor or a crank triggered ignition. Most of the newer ignition systems have a built in start retard that has to be wired into the start button circuit and will retard the timing about 20 degrees during the start process and will stay in up to around 1200 RPM. Some folks swear by these and others swear at them.

    I have a friend with a 496BBC that can't use the start retard function because it makes his kick back but I've known others that have used it with success.

    Once an alky engine is up to operating temperature there usually isn't a problem getting it running unless it's stupid lean and in that case you may have more problems than just flywheels.

    On cold starts, ie, below 55degrees or so I usually squirt some gas down the carb to get it running. If this is a fuel injected setup then it has to run on gas long enough to prime the pump and injectors before it will restart without problems. It it's injected and you are having problems with it after it's warmed up, then make sure your mixture is rich enough then if it is you need to pull the fuel shutoff when you cut the engine off. This will keep fuel from running back into the tank and creating the priming problem you'll have to solve to restart it each time. Some drain back, some don't.

  4. #4
    Senior Member RACING JUNKIE curtisreed's Avatar
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    We have both injected and carbed alcohol motors. On cold start up we use carburator cleaner. It is a little less volital than gasoline and seems to work better, you can spay it down the runners and on the throttle plates and it is lighter so the motor picks it up better. On the injected cars I built a primer system that you can pump until the inj. pump picks up fuel when the motor is warm, just bump the button a couple of times when the motor is rolling over.

    We have found that if the motor kicks back it is because (usually) it is too lean, not the main circuit but just the amount of fuel pumped into the intake, need to get more fuel into the intake at start up. One of the biggest problems though is the fuel wants to puddle when you do pump it in. If you use a primer the nozzle needs to atomize the fuel or point it someplace so the fuel gets broken up and mixed with the air. Getting the motor rolling before the ignition is on only helps.

    Hope this helps someone.

    Curtis

  5. #5
    Senior Member EXPERT BUILDER
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    Must be injected, that doesnt happen with a carb, just pump it twice and hit the button and it will fire right up!

  6. #6
    Senior Member RACING JUNKIE
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    Quote Originally Posted by davis419b
    Must be injected, that doesnt happen with a carb, just pump it twice and hit the button and it will fire right up!
    Ahmen !! 30 degrees and mine starts with no help ...
    David Lanning
    IHRA NHRA 387B

    Fleenor Racing Transmission
    419-280-1406
    Lanning Electric
    Complete Drag Car Wiring
    APD Race Engines
    www.apdracing.com

  7. #7
    Senior Member RACING JUNKIE curtisreed's Avatar
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    Quote Originally Posted by davis419b
    Must be injected, that doesnt happen with a carb, just pump it twice and hit the button and it will fire right up!
    Won't argue it is worse with injector. Don't have accelerator system, hence the primer. Usually has to be pretty cold to need help starting the carbed car.

    curtis

  8. #8
    Thanks everybody. New to methenol.


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