Fluctuating Timing

[68n70]

Going to try to solve this problem this weekend and want to be sure I don't have tunnel vision.  My timing is not solid, that is, if you put a timing gun on it at an idle, it will rock back and forward 3 to 5 degrees.  It does it if you bring it up to say 3,000 rpm's also; it varies.  Other than a bad distributor (which is not very old), is there anything else that might cause this? 
Thanks in advance.

[tan top]

worn timing chain ..... but  have also heard that another cause could be the  harmonic ballancer outer ring moving  ...........

[68n70]

Timing chain...there's a possibility.  Thanks!
Anything else?

[Nacho-RT74]

I'm on that... about +/-2º

and having hard vibrations too above 80 Mph... ( and some vibration at 4000 Rpms in N )

http://www.dodgecharger.com/forum/index.php/topic,51545.0.html

BALANCING DAMPER!!! interesting... could it be related

Chain is relativelly new, same as cam sprocket... and dist is totally new.

[firefighter3931]

What you are describing is fairly normal. Worn oil pump drive bushing, worn oil pump drive or stretched timing chain are the usual suspects. Your distributor is new so the bearing & shaft should be fine....allthough those items will cause erratic timing as well.


Ron

[Runner]

id check it with a different timing light.  i chased a jumping timing  problem for a while after i bought a new dial back light then i got out my flaming river light and it was rock steady.

[dodgey]

Mentioned already but, timing chain, wear in dizzy drive, springs in dizzy loose on posts, weak or wrong spring in dizzy not holding timing steady.
New dizzy or recon ?
A little play in a few parts make for timing scatter.

Or are you electronic

[68n70]

Thanks for the responses guys.
It's a fairly new dist and it has a new intermediate shaft.  I can't get the motor to quit "shivering":  at idle it is has a slight erratic shake to it and you can pretty much watch it on the timing when you have a light on it.  And when trying to hold it steady at 3,000 it will actually cycle slightly up and down rpms's. (I don't have a tach so I can't tell you the rpm amount)  It has a new Speed Demon carb and I feel it is pretty much dialed in, and to tell the truth it did the same thing when I had an Edelbrock carb on it.
Plus it is lazy when doing normal acceleration driving (runs ok at wide open, though I've never been very happy with it overall but I think I expect too much!).
I know the timing chain and gear are old so that's a real possibility as to the problem.

[flyinlow]

My engine timing bounces around a couple of degrees. (3000 MILES on chain,drive gear, cam and  dist.)  Think its normal. Newer cars use crank triggered ignition to eliminate this.