Slant Six Forum :: 225 electronic ignition won't start

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225 electronic ignition won't start https://slantsix.org/forum/viewtopic.php?t=40217	Page 1 of 1

Author:	thedeputy [ Thu May 13, 2010 2:07 am ]
Post subject:	225 electronic ignition won't start
Hi Guys, I need some help with this one. I changed the engine in my valiant from 170 to 225. I upgraded the ignition to a mopar 5-pin electronic with the dual ballast resistor When cranking it won't start. As soon as I let go of the key it seems like it's giving one spark. you can hear the engine trying to start a fraction of a second. It's like the coil is building up sparks when cranking but it can't discharge, but when you let go of the key, then it discharges to the distributor I was thinking about the reluctor being faulty, so I tested it. 275ohms I changed the ecu for a 4-pin one (this ecu has worked before in my challenger) no change. changed the coil no difference. When the key is is in the run position I have 6 volts on the coil, and 12 volts on the ecu. I've also cranked it by putting a screwdriver on the starter engine and leaving the coil wire seperate from the distributor but close to the alternator for ground, and there was no spark. The ecu has a good ground. What should I check? any tips are greatly appreciated. Thanks, Antoon

Author:	Charrlie_S [ Thu May 13, 2010 4:14 am ]
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6 Volts on the coil + sounds a little low, but it should be less then 12 volts, as it comes from the ballast resistor. I would check the distributor. Try to move (wiggle) the shaft sideways. There should not be more then a very very small amount of side movement. Then check the gap between the reluctor and the pickup. set it for .008 with a brass feeler gauge. Check the gap on all teeth. With the tightest at .008, the widest should not be more then about .012.

Author:	thedeputy [ Thu May 13, 2010 4:44 am ]
Post subject:
I looked at the gap, and that seemed allright. Is it possible that, even when the resistance from the pick-up coil is good, and the gap is set properly, the pick-up coil could still be defective? Antoon

Author:	SlantSixDan [ Thu May 13, 2010 8:13 am ]
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Stomp and release the gas pedal, turn the key to the "on" position, then go under the hood and carefully use a screwdriver to connect the two terminals on the starter (without touching any other metal with the shank of the screwdriver). Let us know if the engine starts.

Author:	thedeputy [ Thu May 13, 2010 10:19 am ]
Post subject:
Thanks for the tip, but I allready tried that, and that gave no spark coming from the coil. I did however take out the distributor and did some testing. First I looked at the gap, and it looked fine. I measured the ohms, 275 Ohms, so that's fine I also did an AC volts measurement, while spinning the shaft. This came out around 1,5 volts (depends on how fast I spin it) Also did a herz measurement and while spinning constantly I could easily get it to 25 Hz. I readjusted the gap from the pickup coil to .006", and that gave the same measurements as before. My conclusion to this is that the pickup coil and gap are ok, right? What else could be wrong? Does the distributor need to make ground to the engine? Antoon

Author:	SlantSixDan [ Thu May 13, 2010 10:44 am ]
Post subject:
The distributor doesn't require a ground, but if it did it would surely have a fully adequate one just by being installed with the hold-down bolt. Have you verified that the distributor is actually turning, and that it is timed correctly?

Author:	thedeputy [ Thu May 13, 2010 11:33 am ]
Post subject:
When I turn the fan, the rotor is turning as well, So that's good. I set the crank at 10 degrees before tdc with number one cilinder at the end of compression, and then put in the distributor, in the right position for cilinder one to fire, But all that doesn't really matter as long as I don't have a spark coming from the coil. Now that I tested the distributor I think I should check the coil again, and put on another coil to distributor wire. Is there a simple way to test the coil to make sure that it's working properly? Thanks, Antoon

Author:	thedeputy [ Thu May 13, 2010 11:34 am ]
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By the way, does the coil need a ground to function (in other words, does it need to be mounted to the engine?) Thanks

Author:	SlantSixDan [ Thu May 13, 2010 11:52 am ]
Post subject:
Coil does not need a ground, no. To test the coil, remove the primary wires from it. Connect its (+) terminal to +12v with a test lead. Hold the distributor end of the (thick) coil-to-distributor wire about 1/4" away from the engine block or head with one hand while you use the other hand to touch a grounded test lead to the coil's (-) terminal. Each time you remove the test lead from the (-) terminal, you should get a spark jumping from the coil wire to the block or head.

Author:	thedeputy [ Thu May 13, 2010 11:55 am ]
Post subject:
That sounds logical. Thanks, I'll try that. When I know more I'll fill you in. Antoon

Author:	thedeputy [ Sat May 15, 2010 12:31 pm ]
Post subject:
I found some time to check some things out today, and I hotwired the coil like Dan said to. It gave no spark when given a direct battery+ and ground to the alternator, so I tried another coil. Same result. I put the same coil directly on the battery and gave it a + and a ground, and put the sprak plug wire near the negative plug on the battery. This time there was a spark to be seen. So conclusion: -the coil that's on the engine right now is bad -my engine's ground is not good (makes sense since I painted the engine, however I thought I cleaned all the groundkabel mounting points) I'll try to fix this wednesday. When I know more I'll keep you posted Antoon

Author:	thedeputy [ Wed May 19, 2010 11:24 am ]
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Ok Fixed it. She purrs like a kitten. I changed the coil and adjusted the pick-up coil. Improved the ground from the engine to the chassis, and from the engine to the battery. Then I hooked up the distributor, and put a spark plug directly to the coil output and gave the distru=ibutor a spin. Lots of sparks came from the spark plug So I installed the distributor and fired it up. Ran immediately. After some adjusting she runs really good. One question however. I have two distributors with electronic ignition, there is a big difference however between the two regarding the mechanical advance mechanisme. The one I have installed right now can make half the advance as the other one. Why is there a difference?? Antoon

Author:	Fopar [ Wed May 19, 2010 1:26 pm ]
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One has a smaller advance plate than the other one. Like one would be a 9 or 11.5 and the other one has a 13 or 15, if you remove the reluctor and the backing plate you should be able to read the number stamped on the advance plate.

Author:	thedeputy [ Thu May 20, 2010 2:53 pm ]
Post subject:
Ok. I understand the how (when disassembling the dizzy I run right now, I saw there's a difference between that one and the other one), but why? Does the one with the small amount of mechanical advance give more vacuum advance? What's the best timing I should give it. Initial and total. Or should I post a new question in the engine topic? Thanks, Antoon

Author:	Fopar [ Thu May 20, 2010 6:53 pm ]
Post subject:
No, just look here http://www.slantsix.org/forum/viewtopic.php?t=38471

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