New harminic balancer , new crank seal?

[ZedOfZardoz]

Targetmaster 350 SBC, I'm changing my harmonic balancer for one with the correct timing mark. I saw someone say online thay you also NEED to change the crank seal while down there, is this true? Thanks

 

[Fox80]

I would for the two minutes it takes, and the $5 seal I wouldn't chance leaving the old one in

 

[81Regal]

X2 really easy to do without the balancer on the engine, I just did it this last weekend.