I have.two W108 ballast resistors and they look different.One is grey ceramic with 6 ohm stamped.Other is brown ceramic with 3 ohm stamped.Which one is for the 250SE M129 with the original Bosch coil.westsydneyrestorationsbuilds.on facebook
Viktor - the W108 250SE M129 with the original Bosch blue coil uses the 6 ohm grey ceramic resistor.. mercedes-Benz part number 000 545 04 32. Drops the 12V supply to approximately 8V for the points-and-coil ignition system..
The 3 ohm brown ceramic is for the later 1969+ W108 250SE with the optional electronic ignition retrofit (Bosch 0227100200), which uses a lower-resistance coil and needs less drop.
For your car (1968 build per the chassis stamp), the 6 ohm grey is correct. The 3 ohm brown is wrong and will overheat the coil.
If both came off the same car, your car was retrofitted to electronic ignition at some point and then partly reverted to points. Pick one configuration and commit. Mixed will eat coils.
I have.Billy as always thank you.6 ohm grey going in tomrrow.