Edelbrock 1405 carb running rich

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iamtherealJayy

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I know the throttle cable is junk and should be replaced and I’ll get there, the springs work fine but the pedal was hard to press so I changed the skinny spring to face backwards it was to the front of intake. All the vacuum lines are original except the clear one, it came with the vacuum gauge I bought. The pcv is vented to air it doesn’t go to carb anymore, it didn’t originally until I put a stock air filter back on with a spacer but I started seeing oil in the vacuum lines so I removed it and set it back how it was when I got it. What are you referring to by return line? This truck doesn’t have a fuel return line. What is a transmission modulator? The truck has a 4speed manual as far as I know there’s nothing going to the transmission other than the shifter.
 

iamtherealJayy

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Also I don’t know how concerning it is but the alternator doesn’t kick on until the truck sees over 1000 rpm. Then the voltage gauge shows like 16, it’s not in the “danger zone” yet. But it’s riding it fairly close. What could be the cause of this? It’s done it since I got the truck but I never thought anything about it until I’ve rectory started driving it more.
 

Bextreme04

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I can do the aerosol too but the carb isn’t very old since I’ve had it apart and cleaned it up since I did the jets(which are back factory if you wondered) but I thought pcv was a crank vent? Wouldn’t pouring it in that go into the oil and thin it out some? Or am I not understanding how the pcv works? I think the truck has a little blowby, when I had a different air filter on that fed the pcv into the intake I noticed some oil in the vacuum gauge clear line. So I changed the pcv back to the one that came on jt and changed the air filter back to the moroso one then changed the mixture screws for the different filter. I do have one question, what should I do about the exhaust? The passenger side manifold joint has like two screws that go through with a rectangle piece of metal that has been threaded and you run those through to tighten down and then the third part is a stud(not threaded for some reason?) I’ve tried everything from red rtv to jb weld around the stud to get it to stop leaking. It sounds horrendous inside the cab, you can’t hear it much as the truck is going down the road, but inside all you hear is pfft pfft pfft. So the big question is replacement manifold(s) or headers? I don’t want to spend a tremendous amount of money I just want to fix what needs fixed
When I said "pour it into the PCV hose" I meant pull the PCV valve out, unhook the valve from the hose, and pour it slowly into the hose towards the carb. DO NOT unhook from the carb and pour towards the valve in the valve cover. Can you post a pic of the offending exhaust joint? It sounds like maybe you are missing a part that goes from the manifold to the exhaust normally. It is normal to have oil in the PCV line. You should not have oil in a vacuum line. You can keep a good amount of oil out of the PCV line if you have good baffles in the valve covers.
 

SirRobyn0

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sea foam has a aerosol top end spray
I forget about that because we don't carry it at the shop. We just have the pour bottle seafoam, and ACDelco X66A in the aerosol.
Also I don’t know how concerning it is but the alternator doesn’t kick on until the truck sees over 1000 rpm. Then the voltage gauge shows like 16, it’s not in the “danger zone” yet. But it’s riding it fairly close. What could be the cause of this? It’s done it since I got the truck but I never thought anything about it until I’ve rectory started driving it more.
First thing I would not put to much faith in the exact reading the voltage gauge is giving. You might put a volt meter on the battery with it running if you want to see the actual voltage.

It's not uncommon for these alternators to not want to kick on at idle. It's very likely that it will run like that for years to come before failing, but replacement would be the solution.

Personally I would not be to concerned with what you are seeing in that department. At least if it is in fact running at 16 volts there is no computer to be concerned about.
 

iamtherealJayy

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Here’s the exhaust joint, I took it all apart smothered it with red rtv stuck it all back together tightened it next morning left it alone rest of day and then it went fine until the 1/3 of it that doesn’t get clamped blew out and now it has a leak again. 2/3 of them have the bolt going through with a rectangular piece of metal as shown in photos. The third is just a rod coming off the manifold that goes through the plate on tailpipe side. No threads. The other photo is the current pcv, how it was when I got it. The last photo is just an overview of the engine bay.
 

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iamtherealJayy

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Might I add, when going down the road you don’t hear the exhaust leak unless you’re on the throttle and then it gets worse with more throttle but if you’re coasting not touching throttle at all the truck sounds good rides good etc. but the exhaust leak is pretty much all you hear if you’re even breathing on the throttle.
 

iamtherealJayy

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Also the truck dieseled once today out of all the shut offs. It wasn’t as aggressive as last time but lasted longer in my opinion. Last time was like the engine turned over again this time it just kinda kept breathing? I’m not the best as describing things.
 

Bextreme04

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That looks like one of the newer TBI style manifolds. A replacement manifold can be had for pretty cheap and it comes with the studs and proper donut gasket. You can also try to just put the correct donut gasket in and see if it seals... they are just a few dollars at any big box parts store.
https://www.amazon.com/dp/B000C17GOK/
 

SirRobyn0

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Here’s the exhaust joint, I took it all apart smothered it with red rtv stuck it all back together tightened it next morning left it alone rest of day and then it went fine until the 1/3 of it that doesn’t get clamped blew out and now it has a leak again. 2/3 of them have the bolt going through with a rectangular piece of metal as shown in photos. The third is just a rod coming off the manifold that goes through the plate on tailpipe side. No threads. The other photo is the current pcv, how it was when I got it. The last photo is just an overview of the engine bay.
So it's kind of hard for me to make out the details on the exhaust, but in my opinion other than sometimes on exhaust manifold to cylinder heads my personal opinion on red RTV is that it's useless. The only right solution is cleaning up the surfaces, or if they are really bad replacing the down pipe and manifold. That rod with no threads I'm thinking is a stripped out stud.

However I know you don't wanna do any of that. You could try smearing all the sealing surfaces with a product called acousti seal. It's a thick black sticky substance that will seal and take high heat on an exhaust and still has some flexibility. The trouble is nearly no one stocks it anymore, so most counter guys don't have a clue what it is. The Walker PN# 35959, and I can't image that there is any parts store that can't order it. But wear rubber gloves or it'll be on your hands for few days.
 

SirRobyn0

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That looks like one of the newer TBI style manifolds. A replacement manifold can be had for pretty cheap and it comes with the studs and proper donut gasket. You can also try to just put the correct donut gasket in and see if it seals... they are just a few dollars at any big box parts store.
https://www.amazon.com/dp/B000C17GOK/
I agree this would be the best solution and proper repair.
 

iamtherealJayy

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There’s no way of me getting all the rtv and junk off of it. I used red rtv on the exhaust to cylinder head too in the middle since one of them leaked as well. It is sealed now. Is it possible if it’s a stripped stud to thread it and put on a nut? No one ever commented whether stock manifolds or headers were better, I just want simple unbolt and swap. The rest of the exhaust is junk so I’m not concerned about having to change some of it.
 

SirRobyn0

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There’s no way of me getting all the rtv and junk off of it. I used red rtv on the exhaust to cylinder head too in the middle since one of them leaked as well. It is sealed now. Is it possible if it’s a stripped stud to thread it and put on a nut? No one ever commented whether stock manifolds or headers were better, I just want simple unbolt and swap. The rest of the exhaust is junk so I’m not concerned about having to change some of it.
You could certainly try to thread it. The success will depend on how much rust is on the stud.

My answer to headers vs stock manifolds, is it depends on what you want. If you want reliability, there is nothing better than the stock cast iron manifolds. There is a reason they used those heavy cast iron manifolds, they last and last and seal up well when in good condition, and if they warp they can be easily resurfaced on a belt sander. Headers flow better, but they are prone to leaking, cracking and releasing a ton of heat into the engine compartment. Because of the design there can be heat issues with the starter, fuel pump and or ignition wires. Obviously better quality headers will tend to have fewer of these issues.

To me on a stock or near stock engine headers just don't return enough to make them worth while. On a built up engine that needs added flow then yes they might help. On a daily drive or work truck I'd want the stocker manifolds for reliability.

No one size fits all answer, you decide what is best, but that is my best advice.
 

iamtherealJayy

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Are the manifolds something you can get a pair fairly cheap? I’d do just passenger side but the drivers side looks about like if it ever needed a gasket I wouldn’t know what to do I think it had springs or something another. How do I know whag kind of manifold I have to directly replace it? Or would any manifolds work? I have people that can weld but I’d like to avoid welding as much as possible you know?
 

Bextreme04

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Are the manifolds something you can get a pair fairly cheap? I’d do just passenger side but the drivers side looks about like if it ever needed a gasket I wouldn’t know what to do I think it had springs or something another. How do I know whag kind of manifold I have to directly replace it? Or would any manifolds work? I have people that can weld but I’d like to avoid welding as much as possible you know?
I posted a link to the manifold that would be a direct replacement for what you have. $65 shipped directly to your door and it includes the studs/nuts, manifold gasket, and donut gasket. It's a dorman part number, so it is most likely also available at your local parts store under that same part number for a bit more money. Headers are going to be WAY more trouble and require a lot more work to get them to fit. They are not a direct replacement in any way and will require cutting/welding the exhaust.
 

iamtherealJayy

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I’ll look at that and compare to the one I have, I have other 350’s and I even took a manifold off one last night but it looks completely different.
 

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