why dose my 94 blow black then blue smoke then clean up

 

The black smoke is unburned fuel (you probably give a little pedal when starting?)
The blue smoke is oil burning probably bad ring or bad valves.

If it cleans up and doesn't come back there probably isn't a big problem.

Some of the other guys on here are much more expierenced with this stuff

 

probably your oil ring is shot, im currently rebuilding my 12v and one of my oil rings on a piston was completly gone

 

i forgot its onley when iam on it hard dose this change anything?
thanks

 

well i found it after all i changed fuel fillter and the smoke was gone.
i had 10,000on the filter but found gunk in it.
now the for fun.