[ardeprint]

Manifold should NOT be hot enough that you cant keep your hand on it. If it gets too hot it will burn off the paint and that sets off a lot of smoke. I know you noted that you made sure you did not have an air bubble in your system, but a hot manifold is a clear sign of an air bubble in the system. That is, if there is water flowing.

 

[ardeprint]

Did you find the problem?

 

[ardeprint]

This is a long shot.

Are you sure you don't have too much oil? There is an oil breathing hose down there that could be releasing the built up pressure in your oil pan as it heats up and burns. Does it smell like burning oil? I know you mention a plastic smell, but plastic has hydrocarbons in it so... Maybe?

 

[ardeprint]

I will agree with Jim. We need more details on what we are calling "white smoke".

I have the very same generator. I've had white smoke (not steam) in two occassions. Firts time, white smoke caused due to the red paint burning off from the manifold. This happened when I replaced the impeller and an air bubble formed on the manifold which caused the manifold to overheat. To avoid this, open the air release valve at the top of your manifold. It should be a butterfly looking valve. Run the genny and open the valve until liquid comes out. Don't do this with a hot engine! Make sure its still cold. You can also pump the ruber hose coming out of the heat exchange and into the exhoust manifold using your hand until water flows out.

The other time I had white smoke is when I burned the windings from my back end (electrical generator part of the genset). Needless to say I hope the later is not your situation.

Give us a smoke description to better help, but here are some of my experiences. I hope they help.