Transistorized Ignition

[Meiang]

I have been going through a lot of my collection of car bits lately and dusted of this old Bosch ignition system conversion kit from 1970.

It looks and has a description of parts based upon the page (https://www.sl113.org/wiki/Electrical/TransistorIgnition) very similar to late model W113's with a transistorized ignition system.

The coil has Bosch part number 0 221 118 005 and a date stamp 025 (May 1970).
The switching module has Bosch part number 0 221 051 008 and a date stamp 024 (April 1970).

The resistors are the same value and colour as the MB items as well.

Can anybody provide any further information.

[Benz Dr.]

This is an ignition system that still uses points but only as a switching device.  Known as CD ignition, it was popular from the late 60's until about 1974 when full electronic ignition systems began to take over. MB switched over to full electronic in 1976 with a hall effect ignition distributor. 

It looks like you have all of the parts you need except wiring and a proper distributor. As far as I know, that CD box is no longer available and I don't believe anyone can repair them either. They either work or they don't.

[ja17]

A special mounting bracket attached to the bottom of the battery box holds the switching unit. A separate wiring harness connected everything together. There was also a two wire terminal block for wire connections. The ignition contact points, in the distributor, with this system last much longer than in conventional systems. Check under your battery to see if the mounting bracket is still in place.

[Meiang]

I guess one of my key questions is it possible that the switching unit in this kit replace the original switching unit that the cars left the factory with.  Was there anything special about the original Mercedes unit.