The issue I've seen with the 181s I've looked at in the past are related to them being marine engines. Salt water life is hard on them, and the freshwater boats have mostly been sitting outdoors for awhile without the benefit of antifreeze. if I found a fresh take out, I'd consider it. But Like I said, I do have two of the 153s on hand, one of which I've been running in the jeep for the past 4 years.
