Spark, Fuel, Crank but won't start

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Travlr

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C
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Ok fellas I got of work and checked both things. The old spark plug sparked just fine when hooked up and the rotor pointed to #1 at TDC. Any thoughts?
Just because there is fuel to the carb, it does not mean the fuel is being put through the carb properly. Sitting that long may have resulted in gumming up the jets or any number of other issues.
 

mqbaity

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Here she is, I’ve spent the day messing. A neighbor had a known good distributer so I’ve replaced all the components people have suggested. I also poured a bit of good fuel down the carburetor still with no luck. I appreciate everyone’s suggestions so far.
 

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Bextreme04

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Here she is, I’ve spent the day messing. A neighbor had a known good distributer so I’ve replaced all the components people have suggested. I also poured a bit of good fuel down the carburetor still with no luck. I appreciate everyone’s suggestions so far.
The only thing left is compression. Run a compression test. Pull all plugs, insert the compression tester into each plug and hold down the gas pedal to the floor while cranking for a few seconds. Record each PSI reading for each cylinder. Then put a bit of oil into each cylinder and repeat. All readings should be >120psi and within 5% of each other. If you have one or two cylinders reading below 70psi, you just found your problem.

My truck ran well, then suddenly started running rough, then wouldn't start up at all... all within an hour. I fiddled around with it for hours before running a compression test and finding 0 PSI on one cylinder. Pulled the valve cover and one of the springs had broken and let the valve stay open enough that it was getting zero compression on that cylinder. That was enough to keep the engine from running at all.
 

mqbaity

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I don’t mind. I’m actually quite proud of the truck, my great grandfather and grandpa bought the same model and color trucks on separate trips to the dealership back in 76, my pawpaw said his was $7100. @Rusty Nail I wouldn’t mind some tips on the sprucing up the paint as I’m not quite ready to give up on the factory colors yet.
 

mqbaity

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Also compression test was inconclusive, lowest reading was 120, we’re back to thinking timing. My dads got a mechanic buddy who specializes in Chevrolet and apparently was very excited to hear about the opportunity to play with an almost factory 76, so fingers crossed he can nail down the issue come Tuesday
 

PrairieDrifter

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It doesn't matter if the timing is out. It should pop and sputter or something. You need a solid good spark and fuel and a small block Chevy will run.

12v to the distributor, while cranking and key on. Full 12 volts, starter will drop probably to 10 something. Same goes for fuel. It may have fuel, but not in the right places or the correct amount, they take quite a bit of fuel to fire.

Id bet carb.
 

Rusty Nail

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Jester will show up he's a cool dude.
Whatever ya do don't put an Edelbroke carburetor on it that's Madd ghetto.
If you've got carb problems take the effort to rebuild the Quadrajet. They got a dude in here that does it or maybe somebody knows the place to send it. The whole carburetor, not the truck if you don't wanna do it yourself.
I'd start consider buying a new distributor. They can be had really cheap.
Pull one of the wires off the plug and lay it on the driver side valve cover. Crank the engine and see it it sparks.
 

mqbaity

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Gentleman I have a confession. The fella we brought in to look at the truck at first thought it was timing same as us. But after closer inspection noticed an issue with the spark plug wires and choking system on the carburetor. What he thinks happened is that when it originally died on me the chocking system had flooded the engine and in my AHEM "eagerness" to figure out what was wrong I ran the sparkplug wires incorrectly after replacing some of the distributer components resulting in an engine that wouldn't run. Long story short I need to adjust the choke on the carburetor but my truck is once again in running order. I want to thank everyone for their help and suggestions, it would seem I still have a long way to go but this community is a resource I'm glad to have found. As embarrassing as this mistake was its much better than bad news.:doh2:
 

rusted nuts

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Gentleman I have a confession. The fella we brought in to look at the truck at first thought it was timing same as us. But after closer inspection noticed an issue with the spark plug wires and choking system on the carburetor. What he thinks happened is that when it originally died on me the chocking system had flooded the engine and in my AHEM "eagerness" to figure out what was wrong I ran the sparkplug wires incorrectly after replacing some of the distributer components resulting in an engine that wouldn't run. Long story short I need to adjust the choke on the carburetor but my truck is once again in running order. I want to thank everyone for their help and suggestions, it would seem I still have a long way to go but this community is a resource I'm glad to have found. As embarrassing as this mistake was its much better than bad news.:doh2:
 

rusted nuts

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Gentleman I have a confession. The fella we brought in to look at the truck at first thought it was timing same as us. But after closer inspection noticed an issue with the spark plug wires and choking system on the carburetor. What he thinks happened is that when it originally died on me the chocking system had flooded the engine and in my AHEM "eagerness" to figure out what was wrong I ran the sparkplug wires incorrectly after replacing some of the distributer components resulting in an engine that wouldn't run. Long story short I need to adjust the choke on the carburetor but my truck is once again in running order. I want to thank everyone for their help and suggestions, it would seem I still have a long way to go but this community is a resource I'm glad to have found. As embarrassing as this mistake was its much better than bad news.:doh2:
Thanks for letting us know.
 

flyboys

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Gentleman I have a confession. The fella we brought in to look at the truck at first thought it was timing same as us. But after closer inspection noticed an issue with the spark plug wires and choking system on the carburetor. What he thinks happened is that when it originally died on me the chocking system had flooded the engine and in my AHEM "eagerness" to figure out what was wrong I ran the sparkplug wires incorrectly after replacing some of the distributer components resulting in an engine that wouldn't run. Long story short I need to adjust the choke on the carburetor but my truck is once again in running order. I want to thank everyone for their help and suggestions, it would seem I still have a long way to go but this community is a resource I'm glad to have found. As embarrassing as this mistake was its much better than bad news.:doh2:
Outstanding ! I been following along to see what comments you would be getting. Glad your guy was able to figure it out - I to have a fella that loves SB chevys. He’s been a God send for sure.
My continued frustration is my electronic ignition module keeps failing - (3 times in past year) last time it happened on the highway but I was able to get to the shoulder. I carry a spare (now) in the glove box. Called my son to assist (sketchy area). I’m in a suit … but still climbed in the engine bay and went to work. Gotten pretty good and quick at this now BUT she wouldn’t crank after replacing. After about two hours of checking and rechecking I gave up and called a tow truck. Next morning I pop the hood and climbed inside and what did I see!!! I failed to plug in one of the electrical connections in the rear of the distributor cap. UGH!!!! 275.$ tow truck bill bc I forgot to plug up the dang plug!!! Lol. Lesson learned. So you are not along in the oh crap arena!
 

Scott91370

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...I ran the sparkplug wires incorrectly after replacing some of the distributer components...

Glad I'm not the only one! When I redid mine I counted the cylinders like Ford numbers them but knowing where #1 was I went 2 behind it then 3 then 4. 5 being front left then 6,7, 8 being back by the a/c contraption. Was getting horrible backfire but it had to go to the shop for paint so I left it - I was towing it there anyway so no big deal. My friend (the owner of the shop) was like man it runs rough. We found a couple of plug wires out of order. By a couple I guess he meant 6.
 

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