Okay, so long story short, I bought a 2008 S63 just over a year ago… July 7, 2020. The car had way too much oil added. It had over 2X what was needed in the engine. The car had 11.5 quarts pumped out of the engine and it’s still sitting with about 1/2 quart over with 10 quarts. After the oil was put in, the engine was turned on and back off 3 times and ran for a total of less than 10 seconds. The first time it was started it blew lots of white smoke out the exhaust and the RPMS were sitting normally. The second time the car was started the RPMS were sitting a lot higher than normal. The third time the car was started, the RPMS were sitting a lot lower than normal. The car would not start again after it was turned off the third time. The spark plugs were removed and cleaned and the camshaft and crankshaft sensors were all pulled and cleaned as they had oil in them as well. This did nothing. The car has been sitting since early February 2021.

The car was taken to 2 MB shops and they both said that it would not turn over manually with a wrench either. I’ve been told by non-mercedes specialist, that I most likely just bent a rod on both sides, thus keeping it from turning over. Can anyone know what damage may have been caused?

I was told that it’d be close to $10k to rebuild it, and the MB shop tried to sell me a used one for $25k after installation or a new one for $40k lmfao. Picked up the car for $14k total so I think i’m gonna pass on those lol.

However, I have found a 12’ C63 P30 engine, this engine would fit in S63 without an issue correct?

The C63 engine likely will need vehicle-interfacing bits replaced with the dead S63 engine. Oil pan, engine mounting components, exhaust manifolds, fresh air intake ducts, possibly harness and ECU attachment bracketry. Keep the dead S63 engine as a donor for the parts that can't be used, due to fitment, on the C63 engine.

Yes, I planned keeping the dead engine so, other than the different accessories between the engines, which I already have, I won’t need to purchase anything else other than the C63 engine itself correct?

My neighbor is a master mechanic and said he would take a look and assist me in doing the swap ourselves. Another issue I was worried about with this is software having to be reflashed.

@BlownV8 might have some insight into this.

M156 is an M156. You should just need to swap the oil pan and oil pickup. I would think all the components should swap over but you should probably do some more research to make sure. Your engine probably hydrolocked from stuck injectors. Make sure to proactively replace them every 40k miles. They are a known failure point on the M156.