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On Sunday my 68 camaro just stopped running after it was started and ran roughly 1 minute. Have not been able to restart it. I am runnng a msd 6AL controller with the timing box, ss blaster coil to a 8361 pro billet distributor. I have check coil +\- and get 0.5 ohms and + to output peg at 4500 ohms. I get enough spark off the coil wiring to fire my timing light, but can t get the light to fire off any plug wires. I do get a spark at the plug end when I plug a spark plug in to it but the light will not fire. Just seems to me like I don't have enough voltage to fire the light or spark to combust the cylinder. It doesn't even try to start. Verified timing mark at 0 aligns rotor to #1 port. Had some pitting on the inside of the cap which. Cleaned up with steel wool. Not sure where to go next.
 

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On Sunday my 68 camaro just stopped running after it was started and ran roughly 1 minute. Have not been able to restart it. I am runnng a msd 6AL controller with the timing box, ss blaster coil to a 8361 pro billet distributor. I have check coil +\- and get 0.5 ohms and + to output peg at 4500 ohms. I get enough spark off the coil wiring to fire my timing light, but can t get the light to fire off any plug wires. I do get a spark at the plug end when I plug a spark plug in to it but the light will not fire. Just seems to me like I don't have enough voltage to fire the light or spark to combust the cylinder. It doesn't even try to start. Verified timing mark at 0 aligns rotor to #1 port. Had some pitting on the inside of the cap which. Cleaned up with steel wool. Not sure where to go next.
Check the rotor button really good. Ive seen them burn a hole through under the center and arc to ground down the distributor shaft. Also check it for carbon tracing from the rotor conductor to the mounting screws. The fire may not be leaving the rotor. The reason it may fire a plug in the open is because the resistance is low enough in the open but itll be harder to fire under compression. Its for that reason I like to use a spark tester instead of a plug. You can open the tester up to see if itll throw the spark 1" or so.

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Discussion Starter #3
Rotor looks good. No burn marks or holes. There was some blackness on the tip where the spark jumps at the plug pegs but that cleaned off with steel wool.
 

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Race it, Don't rice it!
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Their going to tell you to send it in and for $100 they can test the box for you.

Sand the grounds first, then check the input voltage into the box, disconnect the tach, and check the dizzy reluctor.
 

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Discussion Starter #6
Changed cap and rotor it still a no start. New coil just came in and once hooked up to my spark tester it jumped over 1" . Put on distributor and the car fired right up. Checked resistance on both coils and they registered the same value so I would not trust a resistance check to say it's bad or good.
 

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bentwings
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I've had three 6AL systems on my Willys. Mine all failed with a simple no start. MSD has a specific test procedure in their manual. Follow it exactly. Make sure you have the system wired exactly as they describe. Their tech will tell you to test the coil then replace the coil....$50+ You should be able to get a spark in the test procedures otherwise the box is bad. $250+ So far I've replaced the box three times, coils 4-5, cap and rotor 4-5, wires and plugs ?? I've forgotten. Ever since they went to the digital box it seems there have been problems. There are a bunch of these in our cruise groups and only a couple have been trouble free over the years.

Stepping down from the phantom soapbox. NALOL. ( not a lot of laughs)

Byron
 

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On Sunday my 68 camaro just stopped running after it was started and ran roughly 1 minute. Have not been able to restart it. I am runnng a msd 6AL controller with the timing box, ss blaster coil to a 8361 pro billet distributor. I have check coil +\- and get 0.5 ohms and + to output peg at 4500 ohms. I get enough spark off the coil wiring to fire my timing light, but can t get the light to fire off any plug wires. I do get a spark at the plug end when I plug a spark plug in to it but the light will not fire. Just seems to me like I don't have enough voltage to fire the light or spark to combust the cylinder. It doesn't even try to start. Verified timing mark at 0 aligns rotor to #1 port. Had some pitting on the inside of the cap which. Cleaned up with steel wool. Not sure where to go next.
Frequently this is a grounding and bonding problem. These high energy ignitions need really secure grounds from the heads, intake, block and any remote box locations back to the negative side of the battery. If the ground path is not sufficient the current finds other ways of getting to ground that can be through module, coil or other circuitry.

Bonding is the term used for the quality of the connection, grounds must be free of paint and corrosion such that the lug has solid and conductive contact. For the classic SBC this brings up the subject of how good are the head and intake bolts at providing a ground path for the distributor, coil, and sparkplugs in a high energy ignition environment. Generally Chevy uses a ground strap located near the starter motor for the engine ground an assumption is made that the heads and intake are suitably grounded through their fasteners and perhaps the head gasket. Since these items also have various sealers on them to prevent coolant and oil leakage the bonding may not be sufficient when very high energy aftermarket ignitions are used. This brings the need to insure the heads and intake have suitable individual grounds that are well bonded to these parts and back to either the chassis structure or the battery's ground post. A number 10 wire linking the castings using bolts in utility holes for the heads and intake with a conductive grease on the threads are needed to assure that the ignition system finds a suitable ground path that does not go through any of the electronic equipment. It also doesn't hurt to furnish the distributor housing with a ground jumper as well.

Bogie
 

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Checked resistance on both coils and they registered the same value so I would not trust a resistance check to say it's bad or good.
Coils like any transformer have two sets of windings, the relationship of winding turns between the two coils determines the voltage increase (or decrease with some transformers).
To test an ignition coil, both sets of windings need to be checked for resistance. The first set of winding aka primary winding is easy to test by connecting the meter across the screw terminals on the coil, one lead on one terminal the other lead on the other terminal and reading the resistance, usually .5-2 ohms is a good for the primary winding of a coil. The other winding aka secondary is easily tested by connecting the meter to the coil's negative screw terminal and the coil wire's lug (center of the coil) and reading the resistance, usually 5K-18K ohms (K = thousand) is a good for the secondary winding of a coil.
Hope this helps.
 

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Oops, on testing secondary winding of the coil, I wrote test resistance between the "negative terminal and coil lug", it should have been positive terminal and coil lug.
 
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