samirshah001

2008 S500 with 130K miles - cylinder #4 has no compression ($3000 repair) and mechanic says there is a chance of needing to replace balance shaft ($4000+)
I am looking to sell the car but will be very difficult to sell a car that is not running. So planning to have replace the engine with a used engine from a local junk yard. Engine cost $2000, replacement cost about $1500.

What questions should I ask and what to look for while making this engine swap?

thanks
sam

superpop

Swap it and run.

steveb9771

Engine swap should only be done by someone very familiar with the electronic engine controls. Mercedes uses extreme measures to prevent theft and unless your mechanic has access to a Mercedes DAS system and other information, it is unlikely that a swapped engine will operate. The fact that your mechanic thought your engine had a balance shaft is an indication of non-familiarity with Mercedes V8 engines. Although your engine does not have a balance shaft, it does have an internal timing chain sprocket that might need to be replaced which I assume should not be a major additional expense it the engine is torn down to fix the compression problem.