Fitting the 123ignition to a 1956 190SL

[123Ignitionusa]

I have a friend with a 190 SL 1956 model.
Says he cannot get the 123 ignition to go in far enough to engage the drive dog.
Its total reach is 73.73mm
Can you think why this might be?

[ja17]

I have seen some shorter drive gears. Is it possible the engine has the wrong drive gear (too short)? How about measuring the  length of the drive gear.

[thelews]

Because the base of the 123 is hitting the adjustment/locking plate.  This is on a later model, 1961 and you'd be better off asking the question and doing a search at www.190slgroup.com  The solution is shown in the extended locking plate

[123Ignitionusa]

Well, it turns out it was the pinch plate. In fact he says the plate was broken so he sourced another. The new plate must have been from a different year because it did not interfere with the installation. There is actually a lot of information about how to work around this interference issue on the internet. The write up from your Group is very helpful and a viable solution. Another solution seems to be to simply turn it over. The down side of this is that the accessibility of the tightening bolt is more difficult. If I could get my hands on a good used unit I would commission a run of clamps that would not interfere and keep the tightening bolt accessible and include it with the  purchase. Anyone got one they would like to sell?
Update: New Billet Aluminum pinch plates are available to remedy the fitment issue of the 123ignition.
Ed

[thelews]

Ed, you asked this question on the 190 SL board and I posted a link where you can buy one for $13.

[123Ignitionusa]

Thanks John I will check it out

[123Ignitionusa]

New pinch plates are available for the 123ignition that do not interfere with the installation on the Mercedes Benz