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• ZU.. ZR.. Z.. ZF.. Service Parts List

ZU.. ZR.. Z.. ZF.. Service Parts List

Guten Tag! The Z series mags were made at the German Werks in Stuttgart and were used on export machinery and as OEM by many brands. They were hot, reliable and very well made. The frames were of polished brass or bronze. They were a wound armarure design and suffered from the usual woes of insulation seepage but seemed to perform whan all was not well and even when all was downright ugly. They had well made condensers that seldom failed. These are excellent mags and many survive today after a hundred years in working condition. The impulse couplers were robust and very well made as well. The American Bosch Z series (ZR4 etc) were far more utilitarian and more potmetal and aluminum was used than their German cousins.

The high tension leads were inserted into the distributor cap and retained by small pointed end 3.5MMx.6 metric set screws in the bottom of a pocket. These were great places to collect moisture and cause rusted screws to seize and break. Always use a well fitting screwdriver and if the screws break off the best way we have found is to build a drill bushing that will slide into the pocket center drilled for the tap drill size of the screw and drop in slowly so not to go through the cap, the drop in with the correct metric tap.

Here is some factory parts info to keep yours alive and well.