Edelbrock 1405 carb running rich

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iamtherealJayy

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Filter for? And the tach may just be junk it’s just a cheap one I ordered, when it works it’s perfect(all though it’s clocked at a weird angle not a big deal but still odd) but when it doesn’t work it’s showing completely wrong information. I have it set to 8cyl and when it’s right the truck idles around 7-800 and revs to 4K no problem and then other times it shows it’s idling at 7k and revs to past the shift light lol. I’m still looking into a regulator to set psi to a constant 4-5psi ish. I’ve heard about edelbrock (can’t remember part number but I’ll go fetch the numbers) 2-9(I think) psi regulator. But I don’t recall but I don’t think it came with all the fittings and adapters. Also, with a regulator would you have to plumb in a return line?
 

Rusty Nail

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I'm not smokin' anything on this

LoL

Okay. :rolleyes: That makes one of us...

I'm at valve adjustment - Lemme axe you a question OP.

Is if the same cylinder backfiring each time or no?
Seems like that should be fairly easy to determine? No?

xc_hide_links_from_guests_guests_error_hide_media
 

iamtherealJayy

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As far as I can tell I do t have a backfire now, the truck fires right up and idles fine just has a slight eye irritation if you’re standing behind it. So I’m thinking it’s slightly rich
 

AuroraGirl

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As far as I can tell I do t have a backfire now, the truck fires right up and idles fine just has a slight eye irritation if you’re standing behind it. So I’m thinking it’s slightly rich
I seem to recall this truck had worn advance?
if its got those worn pivots and springs

I would try a generic non smog sprnig kit even if you "still" should replace distributor because ignition timing if you pull some of those systems
 

Bextreme04

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Add catalytic convertors mebbe.
Not if its running super rich.... you'll be buying another set real soon when the first ones burn up.
 

iamtherealJayy

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It’s not super rich, just slightly now. It isn’t bad enough to foul plugs or anything but if you blip throttle up to 2200-2500 rpm repeatedly it pops, truck has mufflers but still has an exhaust leak at passenger side manifold to exhaust joint. I got the leak at the manifold gasket fixed and changed radiator today the truck ran for a good 20 minutes without over heating and drove it around the property. Soon I plan on taking it on a drive down the road about 10 minutes to take the bed off and put on a utility bed and start daily driving the truck. Other than exhaust leak and the sloppy shifter the truck is doing pretty good currently. Still have some wiring things to figure out (windshield wipers, and the air/heat controls don’t work at all I got the blower motor to come on one speed by plugging the wire into a different spot since it was dangling unplugged so nothing major also finicky fuel gauge) I’ve replaced the pin in the shifter and it helped some but the pin at the bottom is worn out and the weld is cracked. Throughout bearing or somethint squeaks some and the parking brake petal doesn’t go down very far before stopping, adjustment maybe? I think that’s all I have for updates for right now
 

iamtherealJayy

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Drove the truck on a (6.3 mile) trip according to speedometer app since the spedo doesn’t work(tach didn’t either so I had no idea how fast anything was moving). Truck drove fine the steering is kinda junky and the shifter is sloppier than I’d like by a lot.. when I arrived I had a vacuum leak (gauge reading around 11) and the truck was idling around 400 with a slight misfire. Off idle truck ran great but at idle was junk. Sounds like it’s coming from drivers side top of engine. And there’s a drivers side valve cover oil leak that’s making the intake manifold wet. Other than these issues the drive went great and the truck sounds great other than massive exhaust leak at passenger side manifold/exhaust joint. Any ideas where to check for vacuum leak? It’s not the front ports on the carb but it’s easy to hear it but I didn’t have any carb cleaner or anything in hand to check around.
 

Rusty Nail

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You could go back over the intake manifold and carburetor ightening seuences - that might help.
New PCV valves are cheap too.
 

iamtherealJayy

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Trucks been running great just got some paint on it and about time to go to work. Although I’m thinking it’s time for an electric choke. I thought for the simplicity of manual chrome would overcome benefits of electric but not anymore. The truck fires right up and idles as long as you’re constantly moving the choke, it’s around 90° F currently so the choke is pulled about half way, just enough to kick high idle to fire up, and then slowly push it open but if you go too fast off high idle it stutters. For less than $100 I can get the electric conversion, but I have no idea what goes into the electric conversion. I’ll put some pics on here since I don’t think you’ve ever seen the k10.
 

iamtherealJayy

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Been driving the k10 for few days now, other than the obvious horrible fuel mileage it’s running pretty well. Except for if you quickly WOT it doesn’t seem happy and hiccups for a second before revving up, is this considered still running rich? Lean? I noticed it when uh trying to spin tires lol. Rev rev floor it and dump clutch and it didn’t go as well as I’d planned, kinda hiccuped then took off with less rpm than wide open. If I’m already rolling and almost floor it than it’ll spin the tires. And easing into throttle it will get up to 4000 rpms.
 

iamtherealJayy

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Here’s some photos of the journey of this truck lol
 

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iamtherealJayy

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AuroraGirl

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Been driving the k10 for few days now, other than the obvious horrible fuel mileage it’s running pretty well. Except for if you quickly WOT it doesn’t seem happy and hiccups for a second before revving up, is this considered still running rich? Lean? I noticed it when uh trying to spin tires lol. Rev rev floor it and dump clutch and it didn’t go as well as I’d planned, kinda hiccuped then took off with less rpm than wide open. If I’m already rolling and almost floor it than it’ll spin the tires. And easing into throttle it will get up to 4000 rpms.
what distributor are you using? it sounds like it could be a worn or sticky advance + check vacuum advance for if it holds vacuum(its not becoming a vacuum leak) you can check it with a hand pump. THe stock weights are made for a smog 78(i presume its stock 78) and what does yours look like?
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this is a stock 78(albeit not a k10) distributor. you are connected to edelbrock manifold vac right? are you on stock manifold, did it have EGR?

I would also say check your ignition components, spark plug to wire interface has dielectric grease on the boots, your plugs ceramics are good, the connections on the end of the plug look righr and the wire isnt "opened", the coil doesnt look rusted out or melted, the module or connectors dont look melted or possibly OE, you dont have a vacuum leak(dipstick and tube, distributor gasket, valve covers, pcv and the right kind of hose, vacuum booster line is booster rated, gasket on carb is okay)

To me, personally, it sounds like it could be a rich condition, but it could possibly be your idle mixture + maybe some old distributor weights and springs or even edelbrock tendancy to hesitate
There are a few things to look at that dont require money(some of the things above) but if you want to look at your carb,
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Is there any play in your accelerator pump linkage?

I forgot to send this reply earlier , but im not checking to see if I finished so hope its good
 

iamtherealJayy

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Dsitributor as far as I know is the original hei, looks like photos you sent, I take manifold appears factory, has the firing order on it. Was an egr manifold but has a block off now. Could distributor gasket cause a vacuum leak? I didn’t replace it when I had the distributor out I didn’t figure it would harm anything such as a vacuum leak. I can check the linkage I don’t recall any play though. The mixture screws are set to the best vacuum I could get, averages 18-20 at around 600 rpm idle. But if you recall I had a random vacuum leak(12 ish vacuum) and truck idled weird and off idle ran fine? I noticed that there’s oil pooling on the intake manifold. I was reading the middle bolts can have oil seep through the threads? Could that be the case? Could that be a vacuum leak?
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