After a Hammer has a lot of “mileage” the parts that hold the Piston Rod to the Ram wear a little. This will necessitate some adjustment to insure proper tension of the Ram Keys. If this condition exists in your Hammer and the Ram Keys have a tendency to drive through too far, add Shims between the Ram Cushion and the Ram Plate.
Note: although the tip isn’t clear about this, the procedure described here only applies to the #4, #3, #2, #1 and #0 series of Vulcan hammers. (An explanation of hammer series is given in the Vulcanhammer.info Guide to Pile Driving Equipment.) The Super-Vulcan Differential Acting Hammers and the single-acting hammers larger than this (which includes the offshore hammers) use a different arrangement in which the “bulb” at the bottom of the piston rod floats between the split bushing and the ram cushion (illustrated in OffshoreTip 15.) Doing what’s described above in these hammers will jam the bulb and bind the hammer during operation.
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