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Old 10-04-2006, 11:49 PM   #1
shane72_383
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Its missing. HELP!!

My truck has had a slight miss for a while now, so i decided to put a timing light on it to get it 100% dead on. Let me tell you first what im running, its a regular old HEI, with an MSD cap and rotor, Accell super coil, and Accell super stock 8mm wires. Ok, so i put the light on it and it does nothing, turns on but doesn't blink? So i figured maybe the wire was to insulated to pick it up, so i put a stock wire on it and tried it again. Still nothing, until i brought it off of idle, then it started to blink but as soon as it dropped below about 2500 it quit blinking. What is the deal? I want to use the light so hopefully i can get rid of the miss but how can i when it wont work. Any help on why its not registering would be appreciated. Thanks
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Old 10-04-2006, 11:53 PM   #2
RSRXION
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Re: Its missing. HELP!!

I'd be curious to know if the coil is getting weak ? Can / will this effect it ?
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Old 10-05-2006, 12:00 AM   #3
shane72_383
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Re: Its missing. HELP!!

It might, but it shouldn't. I dont think???
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Old 10-05-2006, 12:38 AM   #4
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Re: Its missing. HELP!!

Is it the inductive pickup type light that clips over the wire? Make sure the correct side of the clip is toward the spark plug. Maybe try a different light or one that hooks to the spark plug. The coil shouldn't cause the problem. A weak coil would cause more of a miss at higher rpms. Hook the light to a different cylinder wire just to see if it blinks at idle. There may be something causing a lot of resistance in the no. 1 tower on the cap. I know that the super coils take longer to saturate and fire but the light should still show the firing pulses.
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Old 10-05-2006, 09:58 AM   #5
cableguy0
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Re: Its missing. HELP!!

it could be a bad lead on the light. accel wires are known for leaking voltage and lots of it. not for having great insulation. fire the truck up outside in the dark tonight and use a spray bottle to mist water around on the wires you might find your miss.watch for electricity jumping from one wire to another
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Old 10-05-2006, 03:11 PM   #6
shane72_383
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Re: Its missing. HELP!!

Alright i'll check that, any other ideas would be appreciated because i dont have any idea what the deal is. Thanks
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Old 10-05-2006, 06:11 PM   #7
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Re: Its missing. HELP!!

well definately pull the plugs and check them while your at it. chances are you will find your miss by misting water around. it will arc hard and it shouldnt.
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Old 10-05-2006, 11:13 PM   #8
shane72_383
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Re: Its missing. HELP!!

So i figured it out.........kinda. Figured out that the clip that goes on the spark plug wire wasn't clipped on all the way. So i fired it up and it was blinking just fine like it should, so i turned the distributor a little bit and got it to zero on the pointer. And it ran better than ever, so i shut it off to mess with the carb some and got it about tuned, and then went to fire it up and to my dismay it kind of just banged like it does when it has too much advance. I don't understand how the light says that its timed but then it wont start because it has too much advance????? Here's what im running: an aftermarket 383 stroker crank, externally balanced with a 400 balancer, will it matter what pointer is on it? Thanks any help would be greatly appreciated.
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Old 10-06-2006, 04:33 AM   #9
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Re: Its missing. HELP!!

yea the pointer makes a huge difference.if you have the wrong pointer you will be off 20 or 30 degrees.pull #1 spark plug hold a small screwdriver in the spark plug hole touching the top of the piston spin the engine slowly by hand until the screwdriver doesnt get pushed out any further. if your mark is close to zero at that point you have the right pointer if its not you need to get the right pointer
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Old 10-06-2006, 08:06 AM   #10
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Re: Its missing. HELP!!

The old style hei used a vacaum advance didnt they. did you unplug the vacaum advance and plug it before you timed it. just a thought.????????
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Old 10-06-2006, 08:12 AM   #11
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Re: Its missing. HELP!!

Are you running the MSD. When I added the MSD to my HEI distributor they recommended me to put a low resistance bushing in the cap. If you have that low resistance bushing without the MSD maybe that could be the trouble. The bushing is the spring thing under the HEI coil. Just my $.02
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