If it is not vibrating, you could try a gentle, low rpm drive.
My 79 spit two stock Ford balancers off. The first one just slipped and vibrated like a mother, and I had a 75 mile drive. Fixed it with a junk one, and put an new one on two weeks later.
A couple months later, that new one had the bolt break and just fell off. Did not hurt anything.
No clue why, but I put the original 78 Thunderbird balancer that came on the crank back on it, and it has been there 9 years and spins to 6k at the track. Go figure.