On the back of my motor in white paint pen was "UL 76". Obviously a marking from the factory, prolly the assembler or worker. Anyone else have an idea?

I had those markings on mine too. Can't remember what number now though, theres numbers on my rear plastic under tray also !
Don't know what they mean though.

Most honda engines from the 80's have white marker pen on them somewhere, or at least they did when they left the factory, not sure if honda still do it or if its now been computerised like everything else. It's just the assembly/assemblers details.

Mine's in yellow and says 'LU 77'.
Must be the dyno output as recorded by 'Lu'.

noticed that on mine on the barrels in the v below the carbs thought it may have been scrutineering marks from the past.

I've noticed today my NC30 has marking on rear engine: LE 48 Errrhmm....meaning?

Thank God I thought it was just mine and that I had a rebuilt motor dropped in or something at some point :D

Not sure exactly what theyy mean, but you should have the same markings at the rear of both the top and bottom case. They're used to identify the matched set after line-boring the main journals and transmission bearing housings.

If you have more than one or two cases apart at a time, they are a life saver in making sure you get the right cases mated with each other again.

Mike Norman
G-Force Engine Development