Ford casting number D0OE-6316-B Includes all 1970-71 J or C code 429CJ engines. The D0OE-6316-B harmonic balancer is identified by the 4 bolt holes for attaching the crankshaft pulley. Outside diameter is approximately 6-5/8 inches, and 1-3/8 inches thick. Ford part number D0OZ-6316-B. Has the timing marks on rim. Core charge is refundable when rebuildable D0OE-6316-B harmonic balancer is received by WCCC.
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This is a picture of a 40 year old piece of rubber removed from a harmonic balancer. Notice how dry and cracked it is. The premium black silicone (high temperature) rubber we use is not affected by even continual heat (up to 400 F.) or engine motor oil. The modern material used in our balancers cost about $200 per gallon and will not look like what you see here 40 years later. [You will want to prevent submersion in solvents or gasoline as this type of rubber will absorb solvents.]
The little metal staple you see embedded in the rubber below is for anti static purposes, its job is to ground the inner portion of the part to the outer ring. Over the years the low quality metal used is usually deteriorated beyond usefulness.
Our units have this Beryllium copper spring embedded in them for grounding. This spring boasts 201,000 pounds of tensile strength and will ensure you get no radio static as a result of the balancer.