Was it ran with no or too little oil in it? I assume it wasn't smoking before. The real question is was that because it was so low on oil that there was none to burn, or because you added dino' oil and it previously hadn't been smoking because synthetic oil was in it?
The old 500 engines are known to be virtually bullet proof with little maintenance and, although 1700 hours is a lot, I've seen engines with double that amount of hours. I'd probably start with a compression test to help determine the problem.
The old 500 engines are known to be virtually bullet proof with little maintenance and, although 1700 hours is a lot, I've seen engines with double that amount of hours. I'd probably start with a compression test to help determine the problem.