Balancer slides in on install
I agree with above- the balancer needs to fit at least snug or the single job it has it cannot do. When they machined the crank they may have polished the end snout to remove burrs or drop dent or scratches. They may had put a locking compound like a sleeve retainer on it because they polished it too much. Ask on here for a factory diameter or an un molested crank and check yours. If okay- then check your balancer. I believe the balancer should be .001-.003” smaller than the crank. Might even be less than that like .0015”
Sorry - dampener has 2 jobs- vibration is 1st and turning belts that 2nd. Without the first it cannot do the 2nd for long. lol!