when i was trying to adjust my carb the other day it would actually run better if i left the vac booster disconnected the motor is newly rebuilt less than 1 mile and 1/2 hour one the engine no leaks plenty of power need to adjust t6he valves i took it to an excellent machine shop in spokane called american engine dennis is a geniousdo i have to let it break in more or is this normal it makes it difficult to adjust.