• Home
• Magneto Rx:
• Bosch, American Bosch, and Robert Bosch
• Robert Bosch
• FF4 FU4 FF6 FR4 and friends
• FF4 FU4 FF6 FR4 and friends Instructions

FF4 FU4 FF6 FR4 and friends Instructions

Here is a factory instruction book and parts list. This may help service the different configurations available back in the day.  The instructions for Case Tractor installations is also a wealth of information with a bit more detail not only for case installations.

The screws that hold the plug wires in the distributor plate can be a challenge. Moisture can get into the plug wire entry and corride the small pointy 3.5MM x 0.6 screw that pierces the plug wire. Use a well fitting screwdriver and penetrating oil. They can be seized with a vengeance and break off in the brass insert molded into the hard rubber distributor. This is very typical here in the soggy pacific Northwest. The best way we have found to solve this annoyance is to build a drill bushing that will slide into the pocket center drilled for the tap drill size of the 3.5MM screw and drill it out, then chase the threads.

Here is some info on the distributor plate worth noting.  If the mag is marked FU4/2 it will be a 4 cylinder mag and have two plug wire connections. The distributor plate internally shorts out the two unused posts. Recall we always need a place for the spark voltage to go even if not a spark plug to avoid damaging the coil and high tension insulation components. The shorted posts may be at 90 degrees(Adjacent) to one another (for Hart Parr ) or can be 180 degrees apart (Diagonally) hence the listing for two different distributor plates for the FU4/2 configuration.  

The screws and breaker cover retainer clip that hold the end cap on (illustration 308 and 309) are a special metric thread, 5.5MMx.9. No helicoils available, or taps and dies for that matter. The wisdom is to handle these fasteners with care.