79 Chevy k20 won’t run. Help!

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Weekendmechanic

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So I’ve replaced my coil and module. New plugs wires and cap about a year ago. I’m getting spark. I’ve got fuel. What’s the issue? I’m stuck.
 

hunters628

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What motor is it? Is the timing right? Are you getting any popping or backfiring when cranking?
 

Weekendmechanic

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It’s a 350. And I did open it up and make sure the timing was right. Got the rotor facing cylinder one at TDC. And no I don’t have anything.
 

Weekendmechanic

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I found this. Replaced it thinking that was the issue but it’s doing the same thing. I have 12.5v on both terminals with key on.

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hunters628

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Are you positive your cap is wired correctly. If you have spark and fuel you should be at least getting some popping. How did you verify spark.
 

Weekendmechanic

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I used an inline spark plug tester. And took a video with my phone. I’m doing it by myself which adds some difficulty. And this is my first vehicle that I’ve had to work on so I’m learning as I go. But I’ve doubled and triple checked the wiring order
 

jjester6000

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Did you pull the distributer ever?

If you did, you might have put it in 180 degrees out of phase.

Its a rookie mistake that i've made before.
 

Dmack

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Try a quick shot of starting fluid down the carb. If its close, you should hear it fire momentarily, at least.
 

AuroraGirl

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I had an idiot problem myself once... butteryfly was fully open because throttle spring was not installed... gotta check basics sometimes.
 

Weekendmechanic

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I’ll check that stuff! Thanks y’all. I’ll update you on anything I find!
 

SirRobyn0

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I'll give you one more thing I've seen trick people, even mechanics when using an inline checker that has a light bulb in it. Sometimes you can have an ignition system will light one up one of those type of testers, but it's not strong enough to jump the gap in the plug and light the fuel. Try checking again using a spare spark plug grounded out to something. And / or by a screw type tester where you can see the color of the spark. It should be a nice strong blue color not yellow or weak.
 

AuroraGirl

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I'll give you one more thing I've seen trick people, even mechanics when using an inline checker that has a light bulb in it. Sometimes you can have an ignition system will light one up one of those type of testers, but it's not strong enough to jump the gap in the plug and light the fuel. Try checking again using a spare spark plug grounded out to something. And / or by a screw type tester where you can see the color of the spark. It should be a nice strong blue color not yellow or weak.
My tractor(12 volt converted) that had so little spark ground in the plugs that it barely lit one of the testers. Turns out, the ground for the battery and engine and body(all one) was not good. It got red hot, really, really, really quick. But imagine that, hardly getting 12v or maybe not even at the COIL.
 

1987 GMC Jimmy

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My tractor(12 volt converted) that had so little spark ground in the plugs that it barely lit one of the testers. Turns out, the ground for the battery and engine and body(all one) was not good. It got red hot, really, really, really quick. But imagine that, hardly getting 12v or maybe not even at the COIL.

Farmall, Allis Chalmers, F*rd, John Deere, or other? I recently got me a ‘49 Cubbie and went through that whole thing. They came with magneto ignition but someone converted this one to points. First, no spark because the condenser was grounded to the distributor housing. Second, no start because the timing was off just enough to keep it from starting. I’d never worked on something so simple. I thought late-70s to early-90s GM was fairly simple, but even that’s like entering the Matrix compared to the really old stuff.

OP: that cooked ignition coil lead is usually from slipshod grounding. You’re supposed to have two grounds: the bolt-down wire shown in the pic and a strap with a pin that inserts adjacent to the hot and tach pins in the cap. I don’t remember the OEM ones having the strap, but I know I’ve fried some supposed quality aftermarket units that didn’t come with them. Much better luck with coils that supply the redundant ground.

If you have spark and fuel, something should be happening. Like everyone’s said, make sure you have enough spark. Did you make sure you felt compression out of #1 when you set timing, aligned the mark to TDC, and then adjusted? It’s sounding like a possible 180* out, but it shouldn’t be if it was running, and you didn’t make any radical changes or pull the distributor.

What about cranking voltage drop? Is the starter dragging around? A dying starter can easily rob an ignition system of much needed juice. And all your grounds are good? I’d get a ninth plug you have lying around and rest the plug on the engine for ground and spin it over. Also make sure your cap didn’t crack, and if you have aluminum pins, that they’re not totally oxidized or the wires burned or shorting while cranking. This test is best performed at night when you can see spark touching places it’s not supposed to.
 

AuroraGirl

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1952 massey-harris.. err.. i think the model is 44. Confusing a bit. yeah this was points-ignition 6v, converted to 12v at some point. at least I assume so by the custom bracket and AC Delco alternator running a serpentine belt on it.
 

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