my timing mark on my harmonic balancer comes nowhere near my timing tab without the engine (pre-86 350) crapping out. The timing tab i have is one of those that bolts to the side of the timing chain cover and it has the tab ofset to the side. The timing tab came with the engine in its crate. I have a generic sbc harmonic balancer for 77-93 305 and 350's that i got from the local mr.auto. The timing mark gets nowhere near the tab. The engine does, however, run nice with the timing mark around where the timing tab would be on the newer engines in the center of the timing chain cover. What gives? is the mark on my generic hb in the wrong spot???

 

The balancer may have slipped.. it is 2 pieces seperated by a rubber ring. is it in good shape?

 

its brand new... it is two peices seperated by a ring. maybe i should have checked it before installation. Is there a difference between the tdc of the older 350's verses the new ones with he one peice seal. My timing tab is in a different location off to the drivers-side of the cover, not welded in the center like my one peice 305. Im not in the mood to pull it off to replace it b/c of that.

 

Not too long ago, someone here was having the same problem..Vader gave them some good stuff on the balancer and timing mark. Try doing a search and see if you can find it. I'm not sure if they are different or not...I know some people have used aftermarket timing Tabs, and have problems. The key in the balancer wont let it go on "wrong" But I know there are some variables in the tabs.....Maybe compare your new HB with another and see how the marks line up.

 

one question is that is the tdc for the older engines different than the newer one peice motors? The engine seems to like being timed right where the timing tab on my newer 305 is. Not where the timing tab that gm gave me is. That one osnt in the center, its off to the side. I guess ill have to "feel" where the number one piston is and compare that to the notch on the hb

 

No, you have the correct balancer for your application; you have the wrong timing mark.

Line the motor up to #1 (or #6, if it's easier) TDC, and paint a white line on the balancer where it lines up with your universal timing tab.

 

You can fine #1 cylinder true TDC for your motor with a "piston stop".
And re-mark your balancer or move the timing tab.