Date registered: Feb 2008
Vehicle: 2004 W220 (S430) ; 2001 R129 (SL500) Sport
Location: Alabama Gulf Coast--formerly Charlottesville, VA
Mentioned: 0 Post(s)
Quoted: 1 Post(s)
What leads you to conclude there is no compression?
Assuming your conclusion about compression isn't so, your petrol may have aged and no longer be combustible (unless you put fuel stabilizer in the tank), or the moisture in the petrol settled out (it's heavier than petrol) and is now in the fuel line (it doesn't burn).
It may be some electrical connections have corroded and are no longer carrying fire to places that fire is needed.
If the starter turns the engine freely, then it's unlikely you have any sort of internal catastrophe to fret about.
I'd put as much fresh petrol in the tank as it will hold and jostle the whole lot around then try starting it again. I think old fuel is your problem most likely.
Worst case is the tank has to be pulled and it and the fuel lines have to be drained to get the moisture out. This is unlikely, but it will be expensive if that's the case. Your dealer will most likely propose that out of the box, so if you have an independent garage you trust, I might take it there if new fuel doesn't remedy the problem.
"Don't pick a fight with an old man. If he is too old to fight, he'll just kill you."--John Steinbeck