Ballast unit missing
 

With much thanks to Early S man I know know why my tach doesn't work. No ballast unit. Anybody know where a ballast unit for a 1971 2.2T can be had. Does our host have them. Is there a substitute? Can one be fabricated. I'm sure it is some kind of big resistor.:confused:

bump... anybody?

Okay, I'll go out on limb... I'm fairly sure any 12 volt ballast resistor will do the job. They should be available at automotive supply shops. I replaced the original in my car when I upgraded to a Crane XR700. It came with the Crane coil. It looks very different to the original Bosch being ceramic as opposed to the Bosch alloy and epoxy. I suspect the price will not be too much and not worth fabricating your own.

Where is the thing?

On my 69 I found it on the left side of the engine bay with the relays.

Oops, I have been corrected and informed there are two different kinds, one for the primary coil and another for the tacho... So please ignore me :)

There are actually three ballast units available ... all are three-terminal resistive dividers, all have three 'pigtail wires' with terminals on them, and are all mounted on the relay plate/panel!

For battery-coil ignitions, there are two, both are shallow rectangular boxes:

Beru ... 901.602.852.00

Bosch ... 901.602.853.00

For CDI ignition, there is only one, and it is cylindrical, aluminum can, taller than a round relay ... 901.602.601.00

The CDI and battery-coil devices aren't interchangeable, and I don't have the resistance values.