Harmonic Balancer Timing mark off?
Thread Starter
1st Gear
Joined: Sep 2012
Posts: 1
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Harmonic Balancer Timing mark off?
Hi All,
I've got a 79 with an L48 & HEI
I put the timing light on it today (With vac advance removed and plugged) and I'm very puzzled. It's reading about 16-20* retarded (Best guess). I tried advancing the timing and by the time my timing marks gets to the first (only) retarded notch, the engine putters out and quits. I thought the Harmonic balancers were indexed. Is it possible for it to be off byy that much? Am i missing something?
I've got a 79 with an L48 & HEI
I put the timing light on it today (With vac advance removed and plugged) and I'm very puzzled. It's reading about 16-20* retarded (Best guess). I tried advancing the timing and by the time my timing marks gets to the first (only) retarded notch, the engine putters out and quits. I thought the Harmonic balancers were indexed. Is it possible for it to be off byy that much? Am i missing something?
Burning Brakes
Joined: Aug 2008
Posts: 878
Likes: 55
From: Deep South Denmark
Perhaps you momentarily got confused and thought it was retarded when it's really advanced? I do that sometimes
What way did you turn the distributor to advance it?
What way did you turn the distributor to advance it?
Last edited by Danish Shark; Sep 13, 2012 at 06:19 AM.
Melting Slicks
Joined: Oct 2002
Posts: 2,317
Likes: 111
From: St Louis MO
It's easy to tell if it has slipped. The key is to note whether or not the TDC line on the HD is inline with the keyway slot, or with later HDs (~1969), the TDC line will be 10 degrees counterclockwise from the keyway.
Unfortunately, one needs to remove the pulleys from the HD to tell, but there is another way... The HD has 3 struts which go to the outer ring; there is a 3/8 bolt in the center of each strut and the keyway aligns with one of these bolts... Therefore, the TDC mark should align with the center of one of these bolts (pre-1969), or be 11/16" CCW from that bolt! And you didn't need to remove any pulleys or bolts at all!
Unfortunately, one needs to remove the pulleys from the HD to tell, but there is another way... The HD has 3 struts which go to the outer ring; there is a 3/8 bolt in the center of each strut and the keyway aligns with one of these bolts... Therefore, the TDC mark should align with the center of one of these bolts (pre-1969), or be 11/16" CCW from that bolt! And you didn't need to remove any pulleys or bolts at all!
