3. Loosen gauge holding clamp detail "Retaining Screw' in base. Then slide detail out of position.
4. Insert desired gap size spacer into the top portion of gauge holding detail.
Type CL-249
(.001-.014 Gap Size) .012 Nominal
Type CL-258
(.013-.016 Gap Size) .014 Nominal
Type CL-250
(.015-.018 Gap Size) .016 Nominal
Type CL-277
(.017-.021 Gap Size) .018 Nominal
5. Slide gauge holding detail up to the spark plug. Adjust gauge retaining clamp screw so spacer gauge leaves will
freely enter the spark plug gap openings with minimum center electrode clearance. Locate clamp holding detail
so that spacer gauge engagement extends full length of the center electrode without touching the ceramic
insulator tip.
6. Depress the tool handle so both side electrodes are moderately squeezing the spacer gauge leaves against the
center electrode.
7. Spark plug is now gapped; remove from tool adapter and install next plug repeat above operation. Paragraph
TYPE AV20-3
FINE WIRE SPARK PLUG
GAPPING TOOL
Replacement Service Parts
Type No.
Name
Page No.
CL-303
Stationary Jaw
5612848
CL-304
Movable Jaw
5612849
21