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Discussion Starter · #1 ·
i have a 1980 cj7 with an inline 6
i've never known what this thing is ... it's a small bar thing on the drivers side of my engine, has smaller bars bolted onto the manifold and comes up and runs inbetween the carb and valve cover.
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i've wondered what this thing is for years. i haven't seen it referenced in my shop manual, and i haven't noticed it in pictures of other people's engines.
just wondering if someone can help shed some light on this for me.
what is it? do i need it?
i got a leak at the back of my engine, so i am about to tear into it and replaced the valve cover gasket and exhaust manifold gasket
 

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Discussion Starter · #3 ·
thank you very much for the reply. VERY informative reading.
i quickly found what it's called
apparently it is the "air injection manifold"

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now my question is - do i need it? i guess it's associated with the smog system? is that correct? i don't need to worry about smog regulations. is it better to keep it or remove it? has anyone else dealt with this thing?
 

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The air injection manifold is just one component of the Air Injection System, which also includes a air pump and a diverter valve. Its purpose was to inject air into the exhaust system to create more "afterburn" of unburnt fuel in the exhaust, thereby reducing emissions.

The Air Injection System is one of the fist emissions systems that most guys remove, when they clean up their engine compartments. The air injection manifold can be removed, but you need to plug the holes where it attaches to the exhaust manifold, or else you will have massive exhaust leaks.

Matt
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Many folks whack them off maybe an inch or so

above the connection at the manifold.

Then with some large plies, squish the little tubes flat and

fold them over a time or two.

I reckon it's obvious that you are probably not emissions inspected.

Replace your exhaust manifold with a header---the whole deal will disappear, to include the EGR!

----JEEPFELLER
 

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When I removed my Air Injection System, I just re-used the banjo bolts, that hold the injection manifold to the exhaust manifold, to plug the holes in the exhaust manifold. Use a little exhaust sealant on them, and they will work fine.

I hope the previous poster wasn't serious about replacing your perfectly fine exhaust manifold with headers, just to address this easily solved issue.

Matt
 

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Discussion Starter · #7 ·
thank you guys again for your very informative replies!
if i don't need it, i want to get rid of it. sounds like most people get rid of theirs anyway. i'm not in california, so i don't have to worry about emissions. i'm in hawaii, i just want to turn this into a rock solid island cruiser.

matt, you said you just re-used the banjo bolts that hold the injection manifold to the exhaust manifold.
i'm assuming that is these bolts:
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that was going to be my next question....can i just remove these bolts, remove the air injector thing, and then re-use these bolts...or would i need to get slightly shorter bolts? or just use sealant like you said, and let them stick out or whatever.
you mean sealant like this?

now i am looking at the fig 1k-8 diagram that you posted
on my jeep, where the outlet (??) pipe runs off the air injector manifold to the check valve to the diverter valve...
my jeep doesn't seem to have that. in fact, it looks like it's previously been removed and crudely patched over, because this is the spot on my jeep that corresponds to the picture
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and i don't seem to have an air pump. so i am totally good with getting rid of this air injection manifold.

i am planning to remove the intake manifold and the exhaust manifold anyway, so that i can replace the intake manifold gasket. and fix or make better whatever it else i stumble upon in doing so

i can replace the exhaust manifold with a header if you guys think it's a good idea. i was just planning on disassembling it and cleaning them up and painting them before i put it back together

anything else i should be looking to get rid of, replace, or improve in the process?
 

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Keep those stock wheels! Your '80 has front disc brakes - correct?
 

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A previous owner disabled your Air Injection System, and removed the pump and diverter valve. He just didn't finish the job as well as he could have. I'd remove the air injection manifold, then reuse the bolts your finger is pointing at to plug the holes, using some exhaust sealer on them. No need to replace the exhaust manifold with a header. Just put a new gasket on it, and call it a day.

I'm not sure why a previous owner removed the return line from your fuel system It serves a useful purpose. Read about it in the fuel section of the TSM. I'm betting he also removed the vapor canister, so now your CJ stinks like raw fuel all the time. Am I right?

Matt
 

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A previous owner disabled your Air Injection System, and removed the pump and diverter valve. He just didn't finish the job as well as he could have. I'd remove the air injection manifold, then reuse the bolts your finger is pointing at to plug the holes, using some exhaust sealer on them. No need to replace the exhaust manifold with a header. Just put a new gasket on it, and call it a day.

I'm not sure why a previous owner removed the return line from your fuel system It serves a useful purpose. Read about it in the fuel section of the TSM. I'm betting he also removed the vapor canister, so now your CJ stinks like raw fuel all the time. Am I right?

Matt
You need to reposition that fuel filter.
You want it level and the return line at the 12o'clock position.
 

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Just FYI
Here are pics from my '81 258 with pump and system in working order. Follow path from pump to exhaust manifold, per diagram above, but actual location where it all connects/mounts.

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Just giving other ways to go.

Sorta showing the injection was not a "must keeper" to run right, as it works well with other applications.

My canister is out in the woods somewhere---Mine does not smell like gas? I put gas in mine from time to time....All the way full, 22 gallons......I vented/ extended the green line up high on my firewall with a fuel filter to breathe in either direction.

I was really hoping to hear more about that foreign looking carb in the pic?

Does it get mega mileage, like a constant 18 MPG or more?

-----JEEPFELLER
 

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Discussion Starter · #15 ·
I'd remove the air injection manifold, then reuse the bolts your finger is pointing at to plug the holes, using some exhaust sealer on them. No need to replace the exhaust manifold with a header. Just put a new gasket on it, and call it a day.
copy that. i will remove the air injector manifold and reseal with the bolts and sealer

I'm not sure why a previous owner removed the return line from your fuel system It serves a useful purpose. Read about it in the fuel section of the TSM. I'm betting he also removed the vapor canister
surprisingly, the vapor canister is still down here. i only know what it is because i came across it a few years back when i replaced the fuel tank and was tracing the lines.
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fuel filter does still seem to have the return line going back
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but, as Lumpy Grits noted above, maybe my fuel filter is in an awkward position. actually, now that i really LOOK at it, it does seem super awkward. i mean, why does the hose make a hard elbow to get into the carb? why doesn't it go straight in to the front of the carb? is that normal?
here's looking at it from another angle, looking at the front of the carb. fuel goes from fuel filter and makes a hard turn with the hose to get into the port on the right. what is the port on the left for? why does it not go straight in?
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copy that. i will remove the air injector manifold and reseal with the bolts and sealer



surprisingly, the vapor canister is still down here. i only know what it is because i came across it a few years back when i replaced the fuel tank and was tracing the lines.
View attachment 4132767

fuel filter does still seem to have the return line going back
View attachment 4132768

but, as Lumpy Grits noted above, maybe my fuel filter is in an awkward position. actually, now that i really LOOK at it, it does seem super awkward. i mean, why does the hose make a hard elbow to get into the carb? why doesn't it go straight in to the front of the carb? is that normal?
here's looking at it from another angle, looking at the front of the carb. fuel goes from fuel filter and makes a hard turn with the hose to get into the port on the right. what is the port on the left for? why does it not go straight in?
View attachment 4132770
The smaller line is a fuel return
 

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And teeny weeny port should be rotated to the 12 O'clock position.

Not sure whether the filter should be oriented level, or even level higher than the carb inlet.

Not sure how it was from the factory.

Mine is relocated slightly and higher/ up a little from level/ 12 O'clock return port

----JEEPFELLER
 

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but, as Lumpy Grits noted above, maybe my fuel filter is in an awkward position. actually, now that i really LOOK at it, it does seem super awkward. i mean, why does the hose make a hard elbow to get into the carb? why doesn't it go straight in to the front of the carb? is that normal?
here's looking at it from another angle, looking at the front of the carb. fuel goes from fuel filter and makes a hard turn with the hose to get into the port on the right. what is the port on the left for? why does it not go straight in?
View attachment 4132770
You have weber or weber clone carb and it has the fuel inlet different from the stock location.
 
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