Removed the carburetor for the second time tonight and cleaned per. the carburetor cleaning thread (THANKS FORURM MEMBERS!), anyway I soaked the parts in carb cleaner and destroyed the little O-Rings. Are the very small O-Rings necessary for the Carburetor to run properly? There are two; one on the main jet housing/seat and one on the Pilot Air Adjustment screw. Also I have seen 1-3 turns for the Pilot/Air screw; what is the best for a 1998?