Apologies if this has been asked before but I did try a search and found nothing so thought I'd ask the experts for some advice........
So, the Kawasaki Z400J had been sitting unused and full of fuel in the carbs for 39 years. I stripped and cleaned the carbs and bought new Keyster kits although I cleaned and used the old jets in the end. The carbs were cleaned four times in the utrasonic cleaner using ali and zinc cleaning solution.
Back on the rebuilt motor and it refuses to run unless on choke, turn off the choke and it dies. It also hangs on the throttle when revved. This points to a classic pilot circuit blockage or an air leak (or both). I have now replaced the inlet rubbers as they were a bit hard. The new parts are pattern carb to cyl head rubbers and new carb to airbox rubbers so they should be good and have no air leaks but still the problems persist.
It looks like the carbs will have to come off again for another inspection and clean
. When i inspected the pilot jets I could not see right through them although the holes on the sides were clear. I passed a carb cleaning wire through the jet but it stops dead halfway up (just beyond the holes in the side of the jet). This applied to all four pilot jets so I thought there is a deliberate factory set restriction at this point? Is my thinking correct or should the drilling in the jet be clear from top to bottom and what I though was a restriction for fuel metering ids actually crusty old petrol deposits that needs clearing out?