Where are you located? Perhaps a forum member can take a look or suggest a good independent mechanic in your area to look at the problem.

If the engine is wet, can you determine what the wetness is? It is most likely oil or diesel fuel. Oil can escape from the oil filler cap and spread around, especially on the valve cover. Diesel fuel can weep/leak from the fabric coated return fuel lines running between the injectors. Excess of either of these can cause smoke if they hit a hot surface like the exhaust manifold. If the return fuel lines are leaking, I would suggest replacing these right away. That is a very inexpensive fix.

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