The Tillotson Welch or Soft Plug is commonly covering the low side fuel circuit well.
In some cases, the welch plug covers the high circuit and, in rare cases, the nozzle. The factory's stock plug is covered in epoxy resin, but it is not necessary for doing a rebuild. The welch plug is installed using our 753 welch plug installation punches. Using our punch the welch plug expands against the carburetor fuel well and holds it securely in place.
179-59 OE Tillotson .345" Welch Plus Fits most HS Model Carburetors