Wasp engine stalls on idle

I have a ‘53 Wasp, 262 ci motor. Had carby (Carter WDO) and fuel/vacuum pump rebuilt with new kits. Carby idle jets and float are set correctly. Ignition timing correct. Inlet manifold nuts tight. The motor runs smoothly with the accelerator pedal pressed down but dies a few seconds after I take my foot off i.e. the motor won’t idle. Can anyone suggest a solution please?


  • You have a vacuum leak or no fuel on your idle circuit

  • stevepet
    stevepet Member
    edited November 2023

    want to try putting my carb on? Not using at moment.

  • lostmind
    lostmind Expert Adviser

    Plug the vacuum hose to wipers at manifold and recheck

  • eddiehudson
    eddiehudson Senior Contributor, Member

    Keep turning the idle screw in until you can get it to idle without your foot on the gas.

  • I found the cause of my badly idling Wasp engine. Damaged brand new spark plug straight out of the box. No gap at all! I never bothered to check. I wonder how many people check the gap on a brand new reputable brand plug. Most would just screw it straight in right? So all that expense and work rebuilding carb, fuel pump and distributor could have been avoided. A lesson learned. Anyway thanks to all for your helpful suggestions. Bill.

  • Told you to check gaps. :)

  • railknight
    railknight Expert Adviser

    So, was it just one spark plug that caused the engine not to idle?

  • Always check gap on new plugs....they do not set gaps on the plugs. I've had new plugs right out box that I gapped and they were no good,and that was 40 yrs ago, can't believe they would be better today.

  • Yeah quality definitely isn’t any better today on anything accept maybe oils lol