Ignition Timing is Messed Up
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Ignition Timing is Messed Up
HI All. I had my engine rebuilt in my 85 GSLSE. I restabbed the dizzy and have it running, but it doesn't idle all that smooth. It does die at a stop light and has poor power on acceleration. I checked the timing to dial it in and noticed the L1 and T1 is reading the SAME mark! And the L2 and T2 aren't even showing a mark. On the install, I cleaned and repainted the marks so I can see them clearly. I even added a white mark in case I was going past the yellow.
Anyone seen this or know what I'm doing wrong??
Anyone seen this or know what I'm doing wrong??
#4
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The alignment of the dizzy relative to the engine shouldn't really be the issue here since the leading timing mark is near where it's suppose to be. You more likely want to be looking at the trailing timing adjustment which is done by loosening two screws on the trailing vacuum advance diaphragm and pushing/pulling it to adjust timing relative to the leading mark. Granted in the middle of the adjustment range should be pretty close to the factory 20 degree retard, and I'm not sure if it's actually possible to move it more than +/- ~10 degrees from spec, but perhaps you might have accidently messed with it when servicing the dizzy or something? Did you have the dizzy apart recently or have you not touched it since it was last running?
If the trailing adjustment ends up being all well and good it's also possible that your timing light is picking up cross-talk from the leading wire. Usually you'd see a combination of both leading and trailing pulses in such a case but it's not impossible, though I would say this is unlikely. Other than that I'd just check over everything and make sure no leads or coils are swapped around. One last thing to note is make sure you're setting the timing with the vacuum advance lines unplugged and capped (the lines themselves that is, not the diaphragms) and at normal idle speeds.
TL;DR, stab the dizzy so that the leading is within adjustment range, which is TDC and the dizzy gear aligned with the divot. To sanity check yourself without pulling the whole dizzy you can take off the cap, set the engine to TDC, and the rotor arrow should be pointing towards the right plus or minus a smidge. If the trailing is still being wonky after that something else is the issue.
If the trailing adjustment ends up being all well and good it's also possible that your timing light is picking up cross-talk from the leading wire. Usually you'd see a combination of both leading and trailing pulses in such a case but it's not impossible, though I would say this is unlikely. Other than that I'd just check over everything and make sure no leads or coils are swapped around. One last thing to note is make sure you're setting the timing with the vacuum advance lines unplugged and capped (the lines themselves that is, not the diaphragms) and at normal idle speeds.
TL;DR, stab the dizzy so that the leading is within adjustment range, which is TDC and the dizzy gear aligned with the divot. To sanity check yourself without pulling the whole dizzy you can take off the cap, set the engine to TDC, and the rotor arrow should be pointing towards the right plus or minus a smidge. If the trailing is still being wonky after that something else is the issue.
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