Which W123's had electronic Speedometers?

Only the 1981 300TD.

Thanks Forced. After doing some reading on other forums, it appears that the 1985 300SD also had an electronic speedometer. However, I'm not sure whether the speedometer from the W116 fits in the W123 cluster. Anyone ever tried? If it doesn't I might as well just go to the yard and get whichever late-model MB electronic speedometer I can lay my hands on, because adapting is adapting.

(05-17-2010 11:45 AM)GREASY_BEAST Wrote:  Thanks Forced. After doing some reading on other forums, it appears that the 1985 300SD also had an electronic speedometer. However, I'm not sure whether the speedometer from the W116 fits in the W123 cluster. Anyone ever tried? If it doesn't I might as well just go to the yard and get whichever late-model MB electronic speedometer I can lay my hands on, because adapting is adapting.

Actually all w126's have the electronic speedo.

The w116 speedo head will not fit in the w123 cluster without major modification.

So late model adapting might be the way to go if your looking for an electronic option.


.

The W116 used mechanical.

(05-17-2010 05:43 PM)ForcedInduction Wrote:  The W116 used mechanical.

Sorry, I meant W126. Good to hear the W126 speedometer heads are all electronic, there are some good pictures of a W126 speedometer and instrument cluster in this thread. It looks like I'll be able to cobble it together, I think I'll just go buy one and figure it out. The plan is either to try to hook something up using the speedometer cable to drive a device that will send either a pulse or a voltage signal to a board which will convert it to the appropriate signal for the speedometer, or just generate a pulse directly from the drive shaft or some other rotating driveline component. One idea is to hang a hall effect sensor near the front flex disc so it pulses each time one of the 8 bolts passes by. I would rather do something a little more "solid" like interface with something in the tailcone of the trans, though..