jackg, this diagram shows where the numbers can usually be found on that type of engine:

[Linked Image]

The lower position (that is, on the right side and therefore out of view in your picture) is far more common than the top position.

White smoke may be due to a type of combustion failure caused by water being ingested into the engine. Please check your petrol tank to see if there is any water in the bottom of it. Also see if there is water in the engine's sump. This kind of thing can be caused either by leaving it outside in the rain, or pressure-washing.

Your bedknife looks good in that view, but the top surface is the critical part and we can't see that from the bottom.