Thanks guys for the help. A little history might be in order. Upon purchasing this car, the former owner told me that every once in a while you would need to short/jumper with a screwdriver between the battery connection on the starter motor and the purple lead from the ignition switch. I first suspected that the starter needed to be rebuilt. So, I had a local generator shop rebuild it. The owner said that it had been underwater at one time and the brushes were shot. Obviously he replaced them and checked out the entire circuit plus the solenoid. I trust this shop for I've had him rebuild a number of starters and 40 yr old old tractor generators for me in the past, plus he's been in business for about 50 years.

Craig, the reason it could be the headlight switch is in the following attached schmatic. This is from the MB CD for the car. I was breaking down the componets of the ignition system to issolate the voltage drop. Since the Ignition switch, according to the schematic gets its power from the Light switch, that would be a good starting point.

I thought of the NSS also. I Did move the shifter from park to neutral last night with the ignition switch turned to the start position to test the NSS. Didn't start.

Diesell911, I'd try the glow-plug relay, but the former owner disable the relay in favor of a toggle swithc mounted on the kick panel. So the glow-plug system currently functions independantly of the ignition circuit.

The battery voltage is 12.85 VDC.

I called the generator shop this morning which had rebuilt this starter inquiring about the voltage at the solenoid. He told me that there are many VW's and Mercedes which they have had to put a, "5 wire relay", in because of the low voltage at the starter which he said developes over time. I'll find more about this for and let you know.

Kerry: I agree about the switch. It's 28 years old and could be the problem. Doesn't take much resistance two cause a 3 volt drop. Don't have a problem with cleaning or replacing it.

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