It would be worthwhile running the engine, and seeing how many turns of the main mixture adjustment screw gives the best results. If it is about 1.5 turns, chances are things are working reasonably well.

Remember to clean the small ports in the float bowl retaining nut - these seem to be Tecumseh's version of the main jet and idle jet:
[Linked Image]

Incidentally, there appear to be two screws holding the throttle plate to its shaft. That makes your carburetor a Series 4, not a Series 3 (which only has one screw, same as the choke).

Last edited by grumpy; 17/05/14 07:40 PM. Reason: Add detail