'84 L300 flat-spot - so far have replaced vacum adv', leads, plugs, carby-kit, major-tidy & timing...

happens at about 12-1300 revs. Motor picks up fine after this....

Hi!
Re: Flatspot.
Remove your air filter elbow and with the aid of a torch or other safe illuminating device look down the throat fo the carby whilst operating the throttle. You should see a small stream of fuel being squirted down toward the Venturi nozzle. The size of the hole in the "Discharge nozzle" is extremely small, Hence blocks up with amazing regularity. Should be here that you will find the solution to your flat spot. (Doesnt hurt to "Open it up slightly either!" Does not mean with the aid of a 1/8 drill bit either, Jet (Number)drills are available at all Engineering supply stores.