Carb Rebuild #3 / 50+MPH Achieved

Tonight I rebuilt the carb for the 3rd time. This time I was apparently paying a lot closer attention, I found 3 things wrong:

  1. I had used a washer where the idle cutoff solenoid meets the carb body that shouldn’t have been there. The thickness of this washer was likely keeping the solenoid valve open all the time, allowing it to flood any time it stopped while hot.
  2. The spring inside the accelerator pump was on the wrong side of the gasket. The accelerator pump wasn’t working because the gasket just stayed to one side, with the spring on the correct side it now moves back and forth with the throttle linkage. This gives an extra shot of fuel on initial acceleration, as it was designed to.
  3. The auxiliary jet had been overlooked in previous rebuild/cleanings since it is behind another screw. Once I got it out of the carb I found that it was fully clogged. I cleaned it out with a very fine piece of wire and reinstalled it.

After the rebuild I reinstalled the carb and right away it was able to idle at ~800RPM without any issue, something that was impossible previously. I then took it on two test drives, totaling about 7mi. It did OK overall, it stalled once or twice, but unlike previous trips, I was able to start it right back up. Now I just need to properly adjust the timing/carb since the previous attempts to do this with a broken carb didn’t count.

The test drives gave the chance to verify the speedometer with GPS, it’s very close. I was able to calculate the error based on the difference in tire size vs original and it should be over-reporting the speed by ~3MPH, this is consistent with what I saw on GPS. The top speed on the test drives was a little over 50MPH, to go any faster I’ll have to hookup the tach, do the tune up, and retighten the brake adjusters now that the shoes have had their initial seating from the test drives.

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