[TR] TR4A missing. The saga continues....

[Randall]

>   It still appears to be missing on No 3 as plug is sooty 
> (powdery rather than oily) while others are burning clean.

If the plug is sooty, the cylinder *is* firing.  If it wasn't running at
all, the plug would be wet; the soot is a byproduct of combustion.

Might be a carbon track in the dizzy cap; but I would look at compression
and valves first.  While you are checking valve lash, also look to see if
they all go down by the same amount.  Also swap the plugs around when you
put them back in, as it just might be a bad plug.

Randall