PeachParts Mercedes-Benz Forum - View Single Post - I haven't been this scared since my oil consumption

dpetryk · #14 06-23-2008, 08:45 AM

Deadhead is another term for a condition also known as hydro lock or hydraulic lock. It is where there is liquid in the combustion chamber and the piston cannot compress the liquid thus not allowing the crankshaft to turn. You may not have true hydro lock but the added liquid might make for some very high compression numbers which you feel as a whack. If it was true hydro lock then something has to give - usually the connecting rod or the piston crown etc. I think removing the plugs and cranking the engine will clear up the mystery.