Spark Scatter

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805moparkid

805moparkid

Slant and AFX Guy
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so ive noticed my 73 swinger that trying to time it can be kinda hard... the mark is all over the place.

i checked the timing chain and am only getting two or so degree's movement

gear on the distributor is new

running the stock electronic ignition but with a ballast bypass and 60K Petronix E coil. Blue Streak Cap, 8.5mm wires and NGK plugs. Its also curved to 16 initial, 30 total by 2500, 52 with vacuum adv (Can VC208(11R)).

is common due to the stock box or may it be somethin else? im wondering if this is what is causing my idle miss and ok mileage.

thanks!

P.S. if you want a video i can try and get one tonight so its really obvious.
 

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PanGasket said:
perhaps the balancer has slipped.
Click to expand...

nope its at zero. its not like watching the mechanical curve, a smooth change. this is like 3 pulses at the correct rpm and three way over there and then over here and then somewhere in the middle lol...

i'll get a vid and post it. i think im going to try one of those rev-a-nators, allows me to keep the stock wiring and current coil. With an MSD i would have to get a box AND a new coil.

also the rev-a-nator is much more up to date
 
What springs are you running for advance? My 318 with the MP dist. does that too, I think the springs are too weak.
 
robertob said:
What springs are you running for advance? My 318 with the MP dist. does that too, I think the springs are too weak.
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i dont know which ones my Distributor guy used but usually just pulls the heavy spring and install another light spring. he just has boxes and boxes of springs.
 
uploading the vid on youtube. i cant watch it on my computer so i dont know how it came out but you'll know when i know!
 
Not sure, but looking at the first picture the coil to cap wire takes a sharp bend near heater hose, may be stressed, and failed resistive conductor. If you have a spare, try changing it out for test.
 
KitCarlson said:
Not sure, but looking at the first picture the coil to cap wire takes a sharp bend near heater hose, may be stressed, and failed resistive conductor. If you have a spare, try changing it out for test.
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its brand new and isn't stressed, just looks like it. Wire resistance is fine, passes squirt bottle test, and did it with the old coil and autozone wires.

thanks though
 
Tie the advance with a small peice of wire and that will answer the advance question, but I suspect it's the Mopar module.
 
As you know I don't like to throw parts at a problem, but this may be one of those times

As long as you are convinced it's not a cam / drive problem, nor a distributor gear problem, my guess in no particular order.............

Pickup/ pickup coil, either loose or coil going bad, look carefully for debri (metallic particles) or rust around the pickup / reluctor

CAREFULLY examine the dist. for shaft play, both in the shaft and mechanical.

THERE WAS (I think orange?) a Mopar ECU that did a similar deal some time ago on this board............or at least that's what the member claimed cured it.........replacing the ECU
 
67Dart273 said:
As you know I don't like to throw parts at a problem, but this may be one of those times

i hear ya

As long as you are convinced it's not a cam / drive problem, nor a distributor gear problem, my guess in no particular order.............

yep

Pickup/ pickup coil, either loose or coil going bad, look carefully for debri (metallic particles) or rust around the pickup / reluctor

pickup coil is clean and the coil ohms per spec.

CAREFULLY examine the dist. for shaft play, both in the shaft and mechanical.

its actually tighter than most ive had! probably because this thing only has 105K on it.

THERE WAS (I think orange?) a Mopar ECU that did a similar deal some time ago on this board............or at least that's what the member claimed cured it.........replacing the ECU
Click to expand...

well i know these ECU's arn't that hot and as i said earlier would rather not go MSD.
 
OK so the vid uploaded finally. this was also a low light test and im not to impressed compared to the day time pic quality but its ok.

First thing is at the rear notice the pop's.

Next notice the timing light flashing, its never constant as it should be.

This help?

[ame="http://www.youtube.com/watch?v=sBxjRLM_J6Q"]Slant Six Spark Scatter/ Gopro Black Low Light Test - YouTube[/ame]

P.S. that buzzing is the alternator bearing
 
Almost forgot - what's your gap between the reluctor and pickup? needs to be .008 or less (as little as you can get away with).
 
I cannot tell much from that, but I would not put much stock in what a timing light does.
 
robertob said:
Almost forgot - what's your gap between the reluctor and pickup? needs to be .008 or less (as little as you can get away with).
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.008 on this guy. ive found my 68 like about .010, wont run past .015, runs different below .010
 
I found long ago that side load in the distributor gear wears the busings on a slant 6 distributors. Nylon gears also drop teeth. Since you find the error 3 cylinders apart, that follows 1/2 turn of distributor. I would follow the suggestions for investigating play, or other faults in distributor
 
Is there any way the 2 pickup wires from the distributor could be reversed? If you are using the factory 73 wiring harness and nothing has changed at the distributor side (double-bullet connector) or the ECU side (big 5-pin connector), it should be correct. I know that when people wire their own, like to a GM HEI module, they often get the pickup wires reversed and then the timing is erratic, and the spark fires when the pickup is between reluctor teeth, not aligned with one.
 
BillGrissom said:
Is there any way the 2 pickup wires from the distributor could be reversed? If you are using the factory 73 wiring harness and nothing has changed at the distributor side (double-bullet connector) or the ECU side (big 5-pin connector), it should be correct. I know that when people wire their own, like to a GM HEI module, they often get the pickup wires reversed and then the timing is erratic, and the spark fires when the pickup is between reluctor teeth, not aligned with one.
Click to expand...
now that's sounds like experience talking............Artie
 
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