Double Timing Marks?

[GregL]

My harmonic balancer appears to have two sets of timing marks, about an inch and three quarters apart. If you look from the front, with the keyway at the 12:00 position, the first set is at about 2:00 and the second is at about 3:00.
Any explanation for this?
Thanks, Greg

[paul2748]

The only thing that I can think of is that the balancer was sent out for repair, was completely disassembled and put back together wrong so new marks were set into. Possibility, but not probable. You will have to get # 1 cylinder at top dead center to check which set of marks are correct.

Of course, it could be a factory error??

[GregL]

Thanks Paul.
I also noticed this; if you look close you can see the lower set of marks align with a groove in the front pulley. Could that be a clue?

[paul2748]

Possibility - but I never looked at the timing marks vis-a-vie the groove to see the relationship.