Quadrabog bogs

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SirRobyn0

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@iamtherealJayy That doesn't look like a recent rebuild to me. If it is "recently rebuilt" it's recent as in mileage not time.

The top gasket looks damp that would indicate some seepage, and if it is just that seepage it might not be a big deal, but looking at the overall cleanness or lack there of on the outside of the carb. It's not caked with grim but the idle screws are rusty, the throttle bores are black. I suppose it could be a home rebuild that wasn't the best done.

Check that accelerator pump. Super easy just to look in there and work the throttle with the engine off to see if there is a squirt.
 

iamtherealJayy

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Yes accelerator pump has a great stream throughout whole throttle travel. I admit it wasn’t thoroughly cleaned but last one I rebuild I didn’t clean the outside as much as I should have since it doesn’t matter as much my opinion. It does hint towards it’s been atleast tinkered with since the screws in the vacuum hose arent rusty, the vacuum piece on side is shiny and new looking and there’s still the circle gasket on top(first one I’ve seen that I didn’t put on)
 

Matt69olds

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Does it fall on its face from a standstill? Or just when you stand on it while at speed? Low speed, I’d look at accelerator pump first. Hard throttle while at speed, look at the air door.

Make sure the choke pull off works. It should pull in immediately after startup. In addition to slightly opening the choke after cold startup, it also slows the secondary air door opening. If the choke pull off doesn’t pull in, the air door can flop open causing exactly your problem.

Keep in mind, there is a tiny orifice built in the pull off. If you check it with a hand vacuum pump it will leak down.

There is also a spring and set screw to adjust tension on the air door. Usually those are set pretty tight. It’s possible someone screwed around with it. If the pull off works, try tightening the tension spring a little. Watch a couple YouTube videos on airdoor adjustment, make sure you’re comfortable with what you are doing. If the screwdriver slips off the screw and all the tension is lost it’s kind of a pain to get everything back together.
 

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Alternator doesn't work as it should? You could be losing voltage to the distributor.
It’s a supposed freshly rebuilt quadrajet. Supposed? I have my doubts.
@Paladin will tell you to get a Holley.
Check your vacuum advance & timing. Since it starts ok, I'd say the initial is fine.
Forgot to add, check the torque on your intake bolts; think vacuum leak.
Edelbrock carb in my opinion. Never a lick of trouble and I have used them for almost three decades. I even have a few old Carter AFB that are on some of my classic cars. Excellent carbs and easy to tune and rebuild. Not a fan of Holley carbs unless I am in a race car. Street wise, you can’t beat an Edelbrock with the electric choke. But hey, it’s just my option but I have owned almost 400 cars/ trucks in 35 years and about 99% were classics. I own 23 right now. All but 4 are carbureted. I gave about 20 Holley carbs away about 15 years ago for free.
 

BearKing

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I figure these might be beneficial somehow
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It always starts right back up, it does have a sight puff of smoke when it starts back(darker color) easing into it won’t stall it as quickly but it still doesn’t like full throttle.
I see your problem. Those Croc shoes. Haha
 

iamtherealJayy

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It does it whether I’m rolling or stopped it’s just easier to do it from a stop where I was, I did it going down the road at the guys house aswell, I just blamed it on it was still cold at the time. I’ll have to check the choke, I know it works sorta? There’s a high idle when you start the truck if you had to pump the throttle(if it’s been started within a couple days you don’t have to, but I pressed it to check accelerator pump and choke door shut) and the high idle kicks off with next throttle press. I haven’t had to adjust a choke or anything yet since my edelbrock on my 78 has a manual choke. How do I go about making sure choke is functioning properly? Start it and watch what’s going on with the air cleaner off? @BearKing i love/hate the edelbrock on my 78, I’ve had a lot problems from it but it was given to me used, but any adjustments are super easy which I like lol. Hey now nothing wrong with crocs! Those are my work shoes lol @SirRobyn0 gave me the seal of approval to wear them
 

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It does it whether I’m rolling or stopped it’s just easier to do it from a stop where I was, I did it going down the road at the guys house aswell, I just blamed it on it was still cold at the time. I’ll have to check the choke, I know it works sorta? There’s a high idle when you start the truck if you had to pump the throttle(if it’s been started within a couple days you don’t have to, but I pressed it to check accelerator pump and choke door shut) and the high idle kicks off with next throttle press. I haven’t had to adjust a choke or anything yet since my edelbrock on my 78 has a manual choke. How do I go about making sure choke is functioning properly? Start it and watch what’s going on with the air cleaner off? @BearKing i love/hate the edelbrock on my 78, I’ve had a lot problems from it but it was given to me used, but any adjustments are super easy which I like lol. Hey now nothing wrong with crocs! Those are my work shoes lol @SirRobyn0 gave me the seal of approval to wear them
Just messing with you brother. Gotta give a Squarebody brother a ribbing once in a while. Haha.
 

iamtherealJayy

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Wear crocs all summer and boots all winter lol. Crocs make great work shoes other than all the sawdust getting on my socks
 

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So... my first thought after watching that video is you need to adjust the carb. Turn each idle screw in until it lightly bottoms out and then screw each one out about 1-1/2 turns. Start it up and get it warm, then make sure the choke has pulled off and its idling. Then adjust the base idle to about 750-800 rpm(screw on driver side). Then adjust each idle screw out until you reach peak rpm. Adjust your idle screw while you are doing this to keep the RPM around that 750-800 range. Once you have hit the peak rpm and the idle screw is adjusted to hold that 750 RPM, then screw one idle screw in until you get 50-100rpm drop. Adjust the idle RPM back up to 750 and then repeat with the other idle screw to get your 50-100rpm drop. Now you have set the idle to be slightly lean of peak. Now, set your final hot idle to the desired rpm. I prefer 750 on a street 350. It will usually drop down to around 650-700 when in gear.

The final adjustment is to set the high idle once the engine is fully cold. That should probably happen the next day. Just give it a single pump to the floor to set the choke and then fire it up. Adjust the screw on the passenger side to set the initial high idle RPM to your desired amount. I prefer initial high idle RPM to be about 900RPM as it will then climb to around 1200 as it fully warms. Once it fully warms, kick off the choke and see if it returns to your desired 750ish. Once all of that is set, then see if your drivability issues are fixed or still there.
 

iamtherealJayy

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Should I adjust it per rpm or can I do like I’ve always done it by vacuum? I haven’t put a tachometer in this truck yet so I don’t know exactly what rpms it’s turning. But I can for sure tune the carb and see what happens
 

Bextreme04

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Should I adjust it per rpm or can I do like I’ve always done it by vacuum? I haven’t put a tachometer in this truck yet so I don’t know exactly what rpms it’s turning. But I can for sure tune the carb and see what happens
You can try to do it by ear or using vacuum, but from experience I can tell you that it won't be ideal.
 

iamtherealJayy

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I can rig up a tach to monitor rpms and try that way. It’ll have to be after the rain however.
 

SirRobyn0

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So... my first thought after watching that video is you need to adjust the carb. Turn each idle screw in until it lightly bottoms out and then screw each one out about 1-1/2 turns. Start it up and get it warm, then make sure the choke has pulled off and its idling. Then adjust the base idle to about 750-800 rpm(screw on driver side). Then adjust each idle screw out until you reach peak rpm. Adjust your idle screw while you are doing this to keep the RPM around that 750-800 range. Once you have hit the peak rpm and the idle screw is adjusted to hold that 750 RPM, then screw one idle screw in until you get 50-100rpm drop. Adjust the idle RPM back up to 750 and then repeat with the other idle screw to get your 50-100rpm drop. Now you have set the idle to be slightly lean of peak. Now, set your final hot idle to the desired rpm. I prefer 750 on a street 350. It will usually drop down to around 650-700 when in gear.

The final adjustment is to set the high idle once the engine is fully cold. That should probably happen the next day. Just give it a single pump to the floor to set the choke and then fire it up. Adjust the screw on the passenger side to set the initial high idle RPM to your desired amount. I prefer initial high idle RPM to be about 900RPM as it will then climb to around 1200 as it fully warms. Once it fully warms, kick off the choke and see if it returns to your desired 750ish. Once all of that is set, then see if your drivability issues are fixed or still there.
This. Especially the cold run stuff, to me a properly tuned truck is extremely important.

You can try to do it by ear or using vacuum, but from experience I can tell you that it won't be ideal.
I agree with this very much. @iamtherealJayy setting mixture with a tach is the old standby, tuning way that goes back to the dawn of the automobile pretty much I think. We didn't start setting mixture with a sniffer until emissions requirements came along and that was the reason we were doing it like that. We'd of preferred to be doing it with a tach. It's simple and a very accurate way to dial in a carb right, every time. Honestly I don't know anyone in person that sets carbs up with a vacuum gauge, it's just not the way it was done when carbs were everywhere.
 

iamtherealJayy

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I’ll go wire in a tachometer right quick and try to take a swing at playing with the mix screws and report back how far I get
 

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