It is a common problem on some harmonic balancers on car engines. There are sleeves sold for the balancer that press on over the grooved area and provide a new surface for the seal to ride. Maybe one of these would fit.
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5,614 reviews1975-1995 Toyota Pickup Harmonic Balancer Repair Sleeve, 75-95 ...
1975-1995 Toyota Pickup Beck Arnley Harmonic Balancer Repair Sleeve, 75-95 Pickup Beck Arnley Harmonic Balancer Repair Sleeve -- Beck arnley ...
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5,550 reviews1971-1978 American Motors Matador Harmonic Balancer Repair Sleeve, ...
1971-1978 American Motors Matador Timken Harmonic Balancer Repair Sleeve, 71-78 Matador Timken Harmonic Balancer Repair Sleeve -- Timken harmonic ...
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5,614 reviews1975-1978 GMC C15 Suburban Harmonic Balancer Repair Sleeve, 75-78 ...
1975-1978 GMC C15 Suburban Timken Harmonic Balancer Repair Sleeve, 75-78 C15 Suburban Timken Harmonic Balancer Repair Sleeve -- Timken harmonic ...
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5,614 reviews1975-1977 Dodge Royal Monaco Harmonic Balancer Repair Sleeve, 75- ...
1975-1977 Dodge Royal Monaco Timken Harmonic Balancer Repair Sleeve, 75-77 Royal Monaco Timken Harmonic Balancer Repair Sleeve -- Timken harmonic ...
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5,550 reviews1962-1965 GMC 1000 Series Harmonic Balancer Repair Sleeve, 62-65 ...
1962-1965 GMC 1000 Series Timken Harmonic Balancer Repair Sleeve, 62-65 1000 Series Timken Harmonic Balancer Repair Sleeve -- Timken harmonic ...
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