Interesting tool.

Back when I still used the original 55 adjusters, I made my own by grinding the hex drive on a modern lash tool into a straight screwdriver edge. My P&G gapper showed that tightening the jamb nut without moving the screw always changed the lash by a relatively constant amount, if torque used was consistent. Once a precise measurement/calibration is made initially, the old tool's scale likely COULD insure a consistent lash without feeler or dial gauge, if applied jamb torque could be measured accurately somehow.

6 VOLTS/POS. GRD. NW INDIANA

This tool will work with overhead valve engines with screwdriver slots and jam nuts like those on '54 to 56 Y's  It may be difficult to use at the back of the engine, I have not tried it.  It will also work with other engines with similar rocker arms such as the I block 6.  A socket is put on the tool that is used to loosen the jam nuts, the screwdriver blade is turned by the knob.

This is done with the engine not running in the sequence specified in the shop manual or with each cyl at TDC. I would use a standard ratchet to loosen the jam nut but then put the socket on the tool. Loosen the jam nut and then run the rocker ball down so there is no clearance.  Set the friction pointer to zero on the scale that can be seen on the tool. loosen the rocker ball by turning the knob to the proper setting shown on the scale.  Holding the knob steady tighten the jam nut and Voila the lash is set to the spec without the use of feeler gauges or dial indicator.

This is a nice aluminum casting and seems to be in good condition but I don't have instructions or a box and I can't see who made it.

Best offer by Dec 12 takes it.  Shipping by parcel post from L'ville probably under $5.

Doug T

The Highlands, Louisville, Ky.