Just got a 1959 elgin 12hp had good spark and I cleaned the carb. It starts easy but when you throttle down it has a hard misfire, almost like a hard lean sneeze. I again cleaned the carb and checked spark and it still did the miss. I then took the bottom plug wire off and started it and of course it ran bad but the hard miss was gone. I then pulled the top plug wire and started it and the miss returned. Could the condensor be bad? Seems like its dropping a cylinder. Btw points are clean and coils are not cracked. Thanks, Dave
Never say never, but I’ll say the chances of it being the condenser are very slim. I’d rather think it is a lean sneeze. Could be seals as already suggested. And are you sure the idle tube in the carburetor is clean? That’s a mighty tiny hole in that thing.
Long shot – check the condition of the plug wires. Either a broken wire (invisible) or worn out insulation can cause a short or a loss of continuity at certain positions of the magneto plate.
I believe that carb has an air metering low speed circuit if I’m not mistaken. Of course the adjustment is backwards from say a Johnson or Evinrude carburetor. As Frank pointed out, the dip tube that extends down in to the bowl can easily be plugged up. If your’e careful, you can use a torch tip cleaning wire to push out any debris. Be careful, and don’t break it off in there.. I like to use some Quicksilver Power Tune, or some BRP Engine tuner to soak the carb in, followed by a rinsing with regular carb cleaner. Finish with some compressed air to blow out all passages.
Ok guys thoughroughly cleaned and blew out the carb for the third time and lean condition persists, i checked the upper crank seal and seams it might be leaking. Where can i find one? This is a west bend built motor. Thanks dave
If it runs without the lean spit when you pull the bottom plug wire, then it would seem to me that the problem is most likely with the lower crank seal, if there even IS one, or some other air leak having to do with the lower cylinder.
Or maybe the synch and link is a little off and the throttle valve is opening a tad early?
It does have a lower seal. West Bend/Chrysler 901146. The upper one was sold as part of A73144 Bearing cage assy. I would think it could be replaced separately with a stock seal (??)
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