OK I did the search thing and there are some answers out there but I'm still a little worried.

Searches indicated that there's no wrong way to put the pulley/damper/hub assembly back on the crank... (And yes I did it the 'hard'? way and removed the pulley/damper/hub all at once because I couldn't get the damper to separate from the hub... and I have a good puller anyway...)

So the way I understand it, balance is not an issue. The pulley/damper/hub are neutrally balanced and don't have to relate to the keyway in the crank.

But I thought the key was also there to actually secure the hub's location on the crank too! Meaning that the center bolt holds the hub *on* the end of the crank, but the key was the primary 'keeper' that made sure the hub doesn't *spin* on the crank snout. This is the engine accessory drive pulley and I'd think there is some major torque on it, right?

I guess it's unlikely to spin on the crank snout, given how tight it's 'pressed' on there, but still I wanted to get some opinions.

The crank has the key slot in it but the hub does not. However, if you look at the hub carefully, it has a 'witness mark' in the keyway, but maybe that's just from previously being mounted 'over' the crank keyway.

 

You're OK. The purpose of the keyway is to locate the lower timing sprocket. Lining up the witness mark with the keyway would be a good idea but GM engineered the damper without a slot.

 

Only in the case of forced induction where an extra torsional load is placed on the hub is there really a need for a key to keep the hub from spinning. You have nothing to worry about. I do like to line mine up correctly, though.

 

And usually in a SC setup, the crank is multi keywayed as one is normally not sufficient.

 

For an old style roots blower a double key is a good idea - most centrifugal and screw blowers don't need it.

 

I had a gm original hub with a key-way cut. It is very difficult to align the key and hub since there is no start clearance on the hub bore. I have cracked a timing cover due to false key alignment. I have moved to a Pioneer machined hub with key-way (available thru Jegs). A much better piece than the gm stock hub. Easy to align due to bore clearance for key alignment with the remainder for press fit. Good clearance for removal of the Opti also. Yes, I run a D1 Procharger and a crank driven GZ103 Vac pump. HTH. B.

 

Like I said, "usually". I have personally ripped out a single keyway with centrifugal.

 

I saw (firsthand) the ATI damper hubs split with a single keyway, on two high HP blower motors (Baxter - Vortech centrifugal; Madman - ATI centrifugal). They managed to add a 2nd key to Baxter's, without removing the crank from the engine, or the engine from the car. Also added a reinforcing ring to the ATI hub.

 

350350:
Since you already have the hub off and are concerned about the lack of a keyway, have one machined in the hub and put your mind at ease.

 

So I know you're going to read me the riot act for this, but if I don't just put the darned thing back together soon, I'll go without it another summer. It's show time...

When I was pulling the balancer (this time) I actually spun the 'pulley' outer ring on the center hub. So, I'm tightening the center of the puller, holding the pulley portion of the balancer in the other hand, and the center of the balancer slips inside the rubber ring.

I know I need to replace it. It's another $75 and I'm already into next month's power bill putting it back together.

Is it balanced neutrally? Or does the outer ring slipping affect the balance of the entire crank assembly?

 

Its not a balancer, its a harmonic damper. It is neutral balanced. But to be effective as a damper, the outer ring has to be attached to the inner ring by the intermediate hard rubber ring. And to act as a pulley, the outer ring can't be allowed to slip.

 

Suddenly I wish I'd posted this somewhere with less knowledgeable people, who would have said, "Nah, it's fine, spend that extra $75 on beer and broads!!!

Ok ok sure hey I'll just eat toast 2 more weeks into April. *sigh*

Thank You Sir!

 

Raman noodles rule.

 

Eh, I could stand to lose a few pounds anyway... in my olden age I'm not sure even a starvation diet and a fast car can get me laid anyway...