erratic timing on L98
Thread Starter
Intermediate
Joined: Apr 2003
Posts: 35
Likes: 0
From: Crestview FL
erratic timing on L98
I have a stock 85 and with the EST disconnected the timing mark still jumps around. I would expect this with the est connected but not with it disconnected. When connected it seems like the car is hunting for the correct timing. It will even retard the timing to the point it will pop through the exhuast.
I was thinking maybe my ignition control module was going out. Does anyone have any ides?
I was thinking maybe my ignition control module was going out. Does anyone have any ides?
Le Mans Master
Joined: Feb 1999
Posts: 6,172
Likes: 11
From: somers, ny
Does it hold steady when you rev it a little. I noticed the other day that mine would periodicly jump so i was looking at the other side of the damper......for like one beat every 10 seconds or so. Strange. However if i rev'd it a little it would be rock steady. I need to look into it a bit as well. I guess it could be the EST. I'll let you know if i figure anything out and please do the same. Good luck.
Drifting
Joined: Mar 2005
Posts: 1,923
Likes: 0
From: GA
Originally Posted by cutchy
Morley
Is the reluctor ring the same as the pickup coil?
Is the reluctor ring the same as the pickup coil?
You can find a picture here along with a step by step on tearing down your HEI.
http://www.rustpuppy.org/ignition2/Ignition%202b.htm
Thread Starter
Intermediate
Joined: Apr 2003
Posts: 35
Likes: 0
From: Crestview FL
Had time this afternoon to take a look under the rotor. Everything looks pretty new except for some of the plastoc wire covers. They have some cracks in them but nothing major. I did notice that if I try to turn the distributor shaft with my hand I have quite a bit of play. I would say somewhere between +/- 5 degrees. As it turns it rides up and down a bit. Anyone know what the limits on this free rotation should be? I am thinking new distributor gear and shims. Anyone concur?
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Race Director
Joined: Sep 2000
Posts: 17,298
Likes: 33
From: The Top of Utah
What you are feeling is simply the end play of the dustributor shaft. I have mine shimmed to about .008". I'll bet yours is .040" to .050" or more. That is not uncommon. It would be uncommon to have to replace the distributor gear. Check your timimg chain. I found 12° of timing variation, there.
RACE ON!!!
RACE ON!!!
Thread Starter
Intermediate
Joined: Apr 2003
Posts: 35
Likes: 0
From: Crestview FL
Your right. I measured the rise and it is .050". Even if I hold it all the way up I still have some rotation. That would make me think I had some excessive gear lash. You wouldn't happen to know what that lash should be do you?