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All she does is crank but wont turn over. the timing light is not firing neither so I reestablished TDC with a rag and harmonic balancer indicator. lined up the rotor on a terminal and ran my wires in the firing order. there still was no flashing coming from the timing light, the engine just kept cranking without starting. I pulled out the multimeter and traced my 12 V throughout the ignition system and the distributor is getting 12V. So i checked the plugs and the were oily. Will this prevent the engine from firing? I replaced the intake manifold gasket a few weeks ago, and removed the valve covers without changing the gaskets. there was a little oil on the manifold smoking when it was running. I think it came from the valve covers when they were open. The last thybg i did was pull the number 1 plug, connect the plug wire and used the exhaust manifold as a ground, cranked the engine and checked for a small blue spark. there was noneShould I change the gaskets and get new plugs first? Or is there some other tests of spark I can do?
 

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All she does is crank but wont turn over. the timing light is not firing neither so I reestablished TDC with a rag and harmonic balancer indicator. lined up the rotor on a terminal and ran my wires in the firing order. there still was no flashing coming from the timing light, the engine just kept cranking without starting. I pulled out the multimeter and traced my 12 V throughout the ignition system and the distributor is getting 12V. So i checked the plugs and the were oily. Will this prevent the engine from firing? I replaced the intake manifold gasket a few weeks ago, and removed the valve covers without changing the gaskets. there was a little oil on the manifold smoking when it was running. I think it came from the valve covers when they were open. The last thybg i did was pull the number 1 plug, connect the plug wire and used the exhaust manifold as a ground, cranked the engine and checked for a small blue spark. there was noneShould I change the gaskets and get new plugs first? Or is there some other tests of spark I can do?

So you have no spark, correct? im guessing your cap and rotor are good? if so sounds like you have narrowed it down to the coil or the ignition module (hei, right?) if so, try swaping each for a known good unit....
 

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If you don't have a good coil/module sitting around, just grab the whole dizzy from summit for $90 shipped. I just priced a coil and module and it was $55 for stock parts. I figured I wouldn't have to guess at the problem if I got a complete unit. It worked.

Kev
 

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Discussion Starter #4
So you have no spark, correct? im guessing your cap and rotor are good? if so sounds like you have narrowed it down to the coil or the ignition module (hei, right?) if so, try swaping each for a known good unit....


Yea, sorry, HEI module. I think its there is no spark or the oily plugs are preventing the spark from happening ( not sure if thats possible ) they werent dripping from oil, but were oily. So the cap and rotor are just mechanical right, they need a clean contact surface? ill try a new one. So the oily plugs wouldnt prevent the spark?


Thanks

Gary
 

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Nope. It's in the dizzy. Either a bad: rotor, cracked cap, module, coil, or pick up.

Most likely it's a module or coil. You can pull the coil and test with your hayes manual. I've had some that tested bad but worked and vice versa though! The module you can't test at home. Same with the pick up. The rotor and cap you can tell with a visual inspection.

For $90, a high performance HEI and saving a day or two worth of headaches is worth it to me.

Kev
 

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Most likely it's a module or coil. You can pull the coil and test with your hayes manual. I've had some that tested bad but worked and vice versa though! The module you can't test at home. Same with the pick up. The rotor and cap you can tell with a visual inspection.

For $90, a high performance HEI and saving a day or two worth of headaches is worth it to me.

Kev
I agree :thumbsup:
 

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Discussion Starter #7
I agree :thumbsup:
Nope. It's in the dizzy. Either a bad: rotor, cracked cap, module, coil, or pick up.

Most likely it's a module or coil. You can pull the coil and test with your hayes manual. I've had some that tested bad but worked and vice versa though! The module you can't test at home. Same with the pick up. The rotor and cap you can tell with a visual inspection.

For $90, a high performance HEI and saving a day or two worth of headaches is worth it to me.

Kev
Hrm, ok...Im convinced :yes:

So address the oily plugs after I replace the dizzy?
 

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Discussion Starter #9
check out this on ebay Item number: 250391151994 there great guy and gal to do business with.
lol, that thing looks too nice for my engine bay :eek: thanks, ill probably go with it...cant beat the price, but summitt arrives fast
 

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I can't access ebay right now, but if that is a "procomp" dizzy, stay away.

Summit's dizzy's are Mallory brand.

Kev
 

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Discussion Starter #12
Ok, for the time being, I located an OEM replacement unit for $45. Ill grab some plugs. Is there a positive way to test the spark coming from the spark plugs?
 

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Ok, for the time being, I located an OEM replacement unit for $45. Ill grab some plugs. Is there a positive way to test the spark coming from the spark plugs?
Hook a timing light to one of the wires while someone cranks it over. If it flashes you have spark from the distributor.
 

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Ok, for the time being, I located an OEM replacement unit for $45. Ill grab some plugs. Is there a positive way to test the spark coming from the spark plugs?
they sell testers that are basically a spark plug that has an alligator clip to connect to ground. those work great
 

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Discussion Starter #15
Hook a timing light to one of the wires while someone cranks it over. If it flashes you have spark from the distributor.
Hook the timing light up normally?

they sell testers that are basically a spark plug that has an alligator clip to connect to ground. those work great
I saw one for $15, im not cheap but im hoping there is a way to test spark with what I have
 

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Stick the timing light just like you normally would with the spark plug wire clamp on any of the 8 spark plug wires. If you turn the key and the light doesn't light, you have no spark!

Kev
 

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I saw one for $15, im not cheap but im hoping there is a way to test spark with what I have
an old spark plug sitting on a ground point will work too. when buying tools, realize your not going to just use them one time, you will use it for life. :D


and the good thing about the tester one is is forces the spark across a long gap, making sure the coil is outputing enough juice to jump the spark plug gap under high compression. a weak coil can still make a timing light fire...
 

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I'm not one for replacing parts just because you can't figure out the problem. Based on your description and assuming all the connections are good and you have 12 volts at the coil, my first guess would be your ignition module and second would be the coil. You can have your module tested at most major brand parts stores, Schucks, Napa, etc. Call first. If it's good, factory GM manuals have a step by step process listed to check your coil with an ohm meter. If either one are bad, your looking at close to $30 ea. When you've found the problem you can weigh the cost of a new HEI vs the age and repairs needed on yours. I've seen a number of new replacement parts ordered, only to find the problem is somewhere else. I just think it's a good idea to isolate your problem and then make an informed decision. Saves a few $$ occaisionally.

MTNNOVA
 

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In 99% of cases I agree, MTNNOVA. In the case of 25-35 year old ignition parts, I don't. If the coil is bad, the module might not be far behind. The weights are probably hanging up from years of abuse. The cap is maybe a little brittle and the surfaces are corroded. The advance could probably be updated to the better spring/weight kit. If this motor is anything more than a stocker (or there isn't any intention to upgrade in the future), the Summit (Mallory) HEI is a great deal. Good coil, good module, fresh parts.

We're talking $90 versus $30, $60 isn't much on these money pits. And your time is worth something too, which many of us tend to forget.

Kev
 
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