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The Place for Model-A Ford Carburetors

To properly clean out passages, the brass plugs must be removed and replaced.

Removing and Replacing Brass Passage Plugs

  1. Carefully mark the center of the currently installed plug with a fine point center punch.
  2. Drill plug out with about a half size drill and work up with larger size drills.
  3. When approaching the plug O.D. size, the plug will cleanly spin out.
  4. Clean passages out thoroughly. (I bead blast them.)
  5. Select stepped passage plug size that allows small diameter to fall into casting hole, but the large diameter should be in the range of .005 to .010 inch over size. Passage plugs available at most suppliers are dimensioned for Zenith manufactured carburetors. But, some of their sizes will not be correct for many Holly manufactured carburetors. Of course, some casting hole sizes have been modified over the years. I have machined a wide selection of plug sizes to accommodate such conditions.
  6. Apply Loctite on the small diameter of the plug.
  7. Tap plug into place with a small hammer. Avoid too high of impact to avoid cracking the casting.

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