like you are doing fine.

i wouldnt worry about the carbon. it sounds normal. i would just drive it. i would add fuel additive and always buy quality fuel and just go. if the timeing is spot on it would seem that the chain is good. and with 33 mpg your engine must be in fine fettle.

good luck on the trip.

i had a 72 220. it was a very nice car. i have fond memories of driving it. my first benz diesel. and the first of my second and present run of benzes.

tom w

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[SIGPIC] Diesel loving autocrossing grandpa Architect. 08 Dodge 3/4 ton with Cummins & six speed; I have had about 35 benzes. I have a 39 Studebaker Coupe Express pickup in which I have had installed a 617 turbo and a five speed manual.[SIGPIC]

..I also have a 427 Cobra replica with an aluminum chassis.