It sounds like it might not have been driven much...3k miles in 3 years.

Where are you? You might be able to go to a lighter synthetic oil (perhaps 5w40), to aid in cold starting. However, the thinner oil may cause temperamental seals to leak (perhaps aggravated by the synthetic cleaning out deposits that were keeping them sealed).

I'd change both filters (primary and secondary) as a precaution. Any water in the secondary, combined with cold weather, can't help the process. With a new primary, you'll be able to see how quickly it clogs (or if it does), and make a determination if there's an "algae" problem.

Have a local parts store (autozone, etc) load test the battery (and starting system). You're going to want sufficient CCA (cold cranking amps). If it's insufficient, the starter won't spin as fast as it need be, and that will make it more difficult to start. Also, check the battery grounds and the connection at the starter. Can't hurt. In a pinch, you can increase the output of the battery by bringing it inside and letting it warm up to room temperature. Make sure it's fully charged, too. Also, you can let the glow plugs run until the relay kicks off audibly.

Some forum members have replaced the 616 starter with the turbo 617 version for the faster spinning of the engine.

Some of these things are quick and cheap, others are not. You shouldn't have trouble starting the car at 35F. I would hope that compression would not be a problem with 180k miles...

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1982 240D, sold 9/17/2008
1987 300D TurboW124.133 - 603.960, 722.317 - Smoke Silver Metallic / Medium Red (702/177), acquired 8/15/2009
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