Trouble reving the engine

Discussion in 'Engine, Fuel and Exhaust' started by BigBadWulf, Oct 29, 2011.

  1. BigBadWulf

    BigBadWulf New Member

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    Just bought a 1974 XLCH. Got it running today. It idles fine and drives fine, but when I roll back on the throttle it will cut out. After riding for a bit the engine will stop running and won't start again. Don't know what the cause may be. Where should I look for the problem, carb or electrical?
     
  2. HDDon

    HDDon Experienced Member Contributor Retired Moderators

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    Can you give a little more info? What carb are you running? What ignition? Do you have spark after it shuts down?
     
  3. Binky

    Binky Member

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    wonder if the filter on fuel cock is blocked.
     
  4. Jack Klarich

    Jack Klarich Expert Member

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    More info will help you faster, Could be as simple as bad gas and or a carb overhaul, Until u give more details it will be hard to narrow it down:s
     
  5. BigBadWulf

    BigBadWulf New Member

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    Thanks for the reply. The carb is an S&S Super. The bike has been sitting for the past six months so I removed the carb and went though it. The carb seems clean.

    The bike has been converted to electronic ignition.

    There seems to be a spark after the bike shuts down. To me the problem seems fuel related. But I don't know much about Harleys, haven't owend one previously.

    The bike didn't run well when I first got it home. I figured the carb needed cleaning. I took the carb apart and noticed several things weren't quite right. The accelerator jet was pointing outward toward the air cleaner and there was an O ring missing off the main jet. I fixed the accelerator jet and replaced the missing O ring. The bike started right up and idled great. I took it for a ride around the block but it would cut out when I rolled back on the throttle. After a couple of times around the block the bike quit altogether and I pushed it back home.

    Again, it seems fuel related in my limited experience.

    I checked the fuel filter, it seemed clear.

    Don't know how steady fuel should flow from the pepcock or how srong the flow should be. I removed the fuel line in front of the filter and turned the pepcock to on. Fuel flowed but it was a small stream.
     
  6. HDDon

    HDDon Experienced Member Contributor Retired Moderators

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    If you dumped the old fuel out before you tried to start it, and you have cleaned the carb I would look at the petcock. There is a screen around the pickup tubes and it can become clooged with varnish from the old gas. You wil have to remove it from the tank to inspect. It could also be the fuel line itself, with age they can collapse when warm.
     
  7. Binky

    Binky Member

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    totally agree it has happened to me ,i removed the pepcock on mine and as you say it was coated in varnish due to a bad batch of fuel shipped in to New Zealand
     
  8. SledDog

    SledDog Senior Member Staff Member Moderator

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    Be sure to blow out all the passages on the carb. A small piece of trash can block a passage and cause the roll-on problem. Double check you float level. And as others have said flush the tank and make sure there's no trash in the fuel system.
     
    Last edited: Oct 30, 2011
  9. Jack Klarich

    Jack Klarich Expert Member

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    Check your gas cap and or tank vent as well, It would not hurt to run some Se foam or good Quality cleaner through the system to clean the intake also:D
     
  10. BigBadWulf

    BigBadWulf New Member

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    Pulled off the fuel line just after the pet cock then turned the pet cock to on. No fuel flow. . .The problem appears to be with the pet cock. I cleaned it up but decided to order a new one. Thanks for the tips.