Mercury Sable Repair Question
How deep did it go? If the engine was submerged it may have water in the cylinders and the engine is "hydraulically locked) Was the vehicle hot when it went under? if so water will be drawn into the transmission much easily as well and that would be a problem, with out seeing it, i feel that your mechanic is advising you correctly, I have had customers cars which have been drowned, and have been a source of great concern further down the track.
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