timing belt 101

[kbogach]

I finally put everything together and started the engine, thanks to lister
who answered my questions.  But I noticed that now lifters click.  I drove
the car about 2 weeks after I bought it and it seems t me I did not hear it
before.  Engine was not running about 3 weeks while I slowly did timing
belt, cleaning and eliminated vacuum leaks.
As there are always some doubts in my head first thought was: what if the
belt is one tooth off?  It seems to me it would make  pretty noticable
rather than not displacement of timing marks. But ... I want to ask a
question:  what happens if timing is one tooth off? Will engine start at
all?
Oh... another question:  is it normal if piston's top is covered by soot?

Thank you very much.

Konstantin Bogach.