I kept farting around with different batteries trying to improve the start on my old '75 300D. What made the difference was changing the starter when it finally gave out. I didn't know the motor could turn over that fast, and boy did it make a difference in starting the car.

I changed the starter on my '80 240D over Christmas. It now starts on the first crank. I bet you couldn't cycle the key quick enough and not have it start. It's that fast. I replaced it with the heavy duty 300D federal version. From Fastlane at about $133.

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Michael LaFleur

'05 E320 CDI - 86,000 miles
'86 300SDL - 360,000 miles
'85 300SD - 150,000 miles (sold)
'89 190D - 120,000 miles (sold)
'85 300SD - 317,000 miles (sold)
'98 ML320 - 270,000 miles (sold)
'75 300D - 170,000 miles (sold)
'83 Harley Davidson FLTC (Broken again) :-(
'61 Plymouth Valiant - 60k mikes
2004 Papillon (Oliver)
2005 Tzitzu (Griffon)
2009 Welsh Corgi (Buba)