Keep air injection or not?

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sirrus
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Keep air injection or not?

Post by sirrus »

So my attempts to fix air injection system, which started with getting reman pump, then new check and new air injection manifolds with banjo bolts is stuck as I can't remove the two broken banjo bolts. Poured probably a gallon of PB blaster and ATF+acetone in there, broke two extractors - one is still there, the other I tried drilling out, but I can't fit the 37/64 bit (needed for helicoil insert) there even with right angle drill. So at this point I'm ready to take it to the muffler shop since I was thinking about replacing the muffler anyway.

First question - what should I have the shop do about air injection? I guess my options are either try to get those two bolts out, fix the threads and put everything back on or plug/weld all the holes and get rid of pump, tubes and manifolds. Getting rid of AIR looks easier, but there will be no way back and I have all the parts needed for it anyway...

I have emission testing where I live, but they don't do visual inspection besides checking if cat is present. If I get a new cat that doesn't have tube for air from the pump, it should work?
Sometimes we reinvent the wheel not to have more wheels but to have more inventors

1988 Grand Wagoneer - AMC 360 with ProFlo4 MPFI, TF727, NP229 FOR SALE
2021 JLU Willys EcoDiesel - new shiny toy

candymancan
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Re: Keep air injection or not?

Post by candymancan »

I got rid if mine. I still have the stuff in storage.. but with no emissions needed in Va after 25 years. And with 1 manifold broken and welded by a previous owner. I opted to remove the stock air hat and miles of hoses. Reeroute them all cleanly. And plug the last injection tubes i have. Renove the pump and tube going to the cat and plugging the cat end as well. My cat is also newer too doesnt really need that injection tube anyway. Newer cats are better than the old ines.

Plus your old one can sell for 70-80$ in metal scrap yards. Mine did anyway due to its size

Havent seen any change in the engine. Smells the same to me too
1998 Jeep Grand Cherokee 5.9L Limited 219k
1998 Jeep Grand Cherokee 4.0 I6 laredo 430k
1990 Jeep Grand Wagoneer 155k
1976 Jeep J10.. 85k(repaired)

Topic author
sirrus
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Re: Keep air injection or not?

Post by sirrus »

If it wasn’t for emission testing, I wouldn’t bother with fixing air injection in the first place. Just remove it and plug/weld holes. But that’s not my case unfortunately

I’m going to talk to folks at muffler shop what can they do with it because I’m tired of dancing around that manifold and throwing money away on extractors, drill bits and whatever. At that point I’d just pay someone to fix the threads there and be done with it. If that’s not an option, I’ll have to go with removing it and take my chance at the next sniffer test I guess
Sometimes we reinvent the wheel not to have more wheels but to have more inventors

1988 Grand Wagoneer - AMC 360 with ProFlo4 MPFI, TF727, NP229 FOR SALE
2021 JLU Willys EcoDiesel - new shiny toy

candymancan
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Re: Keep air injection or not?

Post by candymancan »

Ive heard people getting good cats and passing with the air injection and stuff off.
1998 Jeep Grand Cherokee 5.9L Limited 219k
1998 Jeep Grand Cherokee 4.0 I6 laredo 430k
1990 Jeep Grand Wagoneer 155k
1976 Jeep J10.. 85k(repaired)

Topic author
sirrus
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Re: Keep air injection or not?

Post by sirrus »

Just got back from muffler shop, they said they'll try to fix that along with new muffler and pipe. Worst case scenario I'll have some stuff to sell as it's not returnable by now :) Now I have to put Jeep back together and get it to the shop

Any suggestions how I can temporarily plug the holes to get it to the shop without towing? For two holes that still have threads I'm going to put regular 9/16 bolts in there with some antiseize, for others I'm thinking smaller bolts with a dab of JBweld to keep it in place. Any better ideas?

I need to drive it for maybe 7-9 miles and I don't want to melt anything under the hood (thinking battery or evap canister which are few inches away from those holes)
Sometimes we reinvent the wheel not to have more wheels but to have more inventors

1988 Grand Wagoneer - AMC 360 with ProFlo4 MPFI, TF727, NP229 FOR SALE
2021 JLU Willys EcoDiesel - new shiny toy

letank
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Re: Keep air injection or not?

Post by letank »

sirrus wrote: Mon Sep 21, 2020 11:53 am Just got back from muffler shop, they said they'll try to fix that along with new muffler and pipe. Worst case scenario I'll have some stuff to sell as it's not returnable by now :) Now I have to put Jeep back together and get it to the shop

Any suggestions how I can temporarily plug the holes to get it to the shop without towing? For two holes that still have threads I'm going to put regular 9/16 bolts in there with some antiseize, for others I'm thinking smaller bolts with a dab of JBweld to keep it in place. Any better ideas?

I need to drive it for maybe 7-9 miles and I don't want to melt anything under the hood (thinking battery or evap canister which are few inches away from those holes)
JB weld will not hold it... I tried as a bandaid until I installed a new air manifold on the passenger side and exhaust manifold as I discovered a large crack when I was checking for leaks. Yes easy out do not work, they break inside. IIRC there is technique where the part is submitted to some high frequence, but the part has to be removed... and in our rigs we know that most exhaust manifold bolts break if not done with care of pb blaster, heat... impact driver and what not...

JB weld has a high temp version which I tried on the kid's honda cracked exhaust manifold for a tease... until I received the exhaust manifold... it did not last either. I cleaned and grinded the metal a bit...

Before I forget, I installed the driver's side version, 3 legs on the passenger side, this is what I had, and I still pass smog, that was 10 years ago!
Michel
74 wag (349 Kmiles... parked, next step is a rust free body)
85 Gwag (229 Kmiles... the running test lab)

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sirrus
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Re: Keep air injection or not?

Post by sirrus »

Thanks for input Michel! Maybe JBweld will hold for 20 minutes, that would be enough.. I just need something to last there and hold the plug/bolt in place so I don't have exhaust blasting out out that hole right onto evap canister.

Now that I think about it - I actually had a drivers side (3 port manifold) on pass side and passed emissions OK, that gives me an idea if we can't get those two holes fixed, maybe I can plug only two and modify the manifold to inject air two two other ports. Less effective, but should still work.

Here's a pic of what I'm struggling with

Image

I tried to drill out the front broken bolt and now it's just a 1/2-ish hole there :) God I hate everything about exhaust by now :)
Sometimes we reinvent the wheel not to have more wheels but to have more inventors

1988 Grand Wagoneer - AMC 360 with ProFlo4 MPFI, TF727, NP229 FOR SALE
2021 JLU Willys EcoDiesel - new shiny toy

Topic author
sirrus
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Re: Keep air injection or not?

Post by sirrus »

So after more reading and thinking I’m leaning towards keeping air injection and getting two holes with broken bolts shut. Two points of air injection should be enough for the system to work

Next question is how to plug those holes - as I understand it welding cast iron is very tricky and can’t be done with manifold on the engine. Taking it off will definitely result in more broken bolts which will send me to the whole new world of struggle :) what I came up so far is to plug holes with high temp putty for exhaust repair and maybe wrap it over with exhaust repair tape so it won’t blow out. I know that’s not the best solution, but I tried tapping a threads in those holes to put a bolt in there and failed miserably. Any other suggestions?
Sometimes we reinvent the wheel not to have more wheels but to have more inventors

1988 Grand Wagoneer - AMC 360 with ProFlo4 MPFI, TF727, NP229 FOR SALE
2021 JLU Willys EcoDiesel - new shiny toy

letank
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Re: Keep air injection or not?

Post by letank »

you can try the jb weld hi temp, it may last a bit of time...
It would take me some time to find what I did 10 or 12 years ago... I pushed some large screw with JB weld normal... when JB weld cooked, it was smelly...
Your case is a bit more challenging... with the broken easy out

The old saying was to turn the exhaust manifold red hot -aka WOT- then apparently the bolt loosen up easily... I have not tried this method to remove the exhaust manifold...

I sprayed PB blaster everyday for a week... no luck... tried knock'er loose a napa product, then freeze off and alternated with a torch... impact driver... a very long crow bar to give enough progressive nudge... tightened up a bit, then loosen it... after 2 weeks of this regimen I extracted all the exhaust bolts... I drilled some access holes in the inner fender to slip the impact driver socket...
Michel
74 wag (349 Kmiles... parked, next step is a rust free body)
85 Gwag (229 Kmiles... the running test lab)
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tgreese
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Re: Keep air injection or not?

Post by tgreese »

Similar idea - The mechanics at the Jeep dealership would take the Jeep out on the local freeway for a high-speed run before removing exhaust manifolds. Rocket hot helped, but the burn potential was high. And these guys were working on customer cars that were only a few years old.
Tim Reese
Maine beekeeper's truck: '77 J10 LWB, 258/T15/D20/3.54 bone stock, low options (delete radio), PS/PDB, hubcaps.
Browless and proud: '82 J20 360/T18/NP208/3.73, Destination A/Ts, 7600 GVWR
Copper Polly: '75 CJ-6, 304/T15, PS, BFG KM2s, soft top
GTI without the badges: '95 VW Golf Sport 2000cc 2D
Dual Everything: '15 Chryco Jeep Cherokee KL Trailhawk, ECO Green
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letank
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Re: Keep air injection or not?

Post by letank »

check these sites, which are what was said above

https://www.onallcylinders.com/2017/10/ ... and-bolts/

http://fiero.nl/forum/Forum2/HTML/140257.html

Yes: inverting a can of dust off , let the pressurized gas out with a cooling effect , wear gloves and face shield, you do not want to breath that stuff
Michel
74 wag (349 Kmiles... parked, next step is a rust free body)
85 Gwag (229 Kmiles... the running test lab)

threepiece
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Re: Keep air injection or not?

Post by threepiece »

For removing the broken bolts, could you drill them with an extended drill?

I have several times created extended drill bits by welding a similar size rod to them. I use a piece of angle to locate the two pieces. For access you may be able to remove the wheel and pass the drill under the wheelhouse. Sometimes bending the wheelhouse out of the way or trimming it. You could do the same extension on the tap if needed.
I used to name my FSJ’s after their previous owners, I realized I had too many with five named Rick.

Dang raccoons again!

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weeegoneeer
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Re: Keep air injection or not?

Post by weeegoneeer »

Sirrus - I need to pass Oregon DEQ as well - I have plugged air holes on my manifolds & the non-air injection cat sold on BJs with their stainless exhaust set — it's a magnaflow I believe and isn't too spendy. Pass DEQ with flying colors, no EGR, manifold vacuum (so more advanced than factory at idle). I think Air Injection had more to do with the catalyst technology back in the day. If it were me, I'd just plug them and get a modern cat. You don't need to maintain tubes and an airpump at that point.

Have never had an inspection in Multnomah County where they confirm original emissions equipment on the motor - they just want to make sure you have a cat with the floor mirror and that the stuff coming out of the tailpipe isn't toxic. Washington County may be harder but I doubt it. At the end of the day it does feel good to not be superpolluting, and be able to do it with modern stuff.
1984 GW

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Re: Keep air injection or not?

Post by sirrus »

weeegoneeer wrote: Wed Sep 23, 2020 8:16 pm Sirrus - I need to pass Oregon DEQ as well - I have plugged air holes on my manifolds & the non-air injection cat sold on BJs with their stainless exhaust set — it's a magnaflow I believe and isn't too spendy. Pass DEQ with flying colors, no EGR, manifold vacuum (so more advanced than factory at idle). I think Air Injection had more to do with the catalyst technology back in the day. If it were me, I'd just plug them and get a modern cat. You don't need to maintain tubes and an airpump at that point.

Have never had an inspection in Multnomah County where they confirm original emissions equipment on the motor - they just want to make sure you have a cat with the floor mirror and that the stuff coming out of the tailpipe isn't toxic. Washington County may be harder but I doubt it. At the end of the day it does feel good to not be superpolluting, and be able to do it with modern stuff.
Thanks weeegoneeer! That sounds reassuring as I was hoping I can get away with modern cat and no air injection. That would simplify things under the hood a lot. Guess another order from BJs is coming up :) Now I have to find someone who needs new manifolds, bolts and reman air pump though

I was actually looking at BJs exhaust kit for some time now - how do you like it? Is it loud or moderate? I'm looking for something on a quieter side, buit I still want to know that I have V8 under the hood :)
Sometimes we reinvent the wheel not to have more wheels but to have more inventors

1988 Grand Wagoneer - AMC 360 with ProFlo4 MPFI, TF727, NP229 FOR SALE
2021 JLU Willys EcoDiesel - new shiny toy
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tgreese
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Re: Keep air injection or not?

Post by tgreese »

weeegoneeer wrote: Wed Sep 23, 2020 8:16 pm...
I think Air Injection had more to do with the catalyst technology back in the day. If it were me, I'd just plug them and get a modern cat. You don't need to maintain tubes and an airpump at that point. ...
Air injection pre-dates the introduction of catalytic convertors. AI will lower your HC count by itself. It's true that the early convertors used and need the O2 overload the AI provides, but I don't know the history of that. Necessity or economy or what.

The air pump is a maintenance headache, which would be good to get rid of if you don't need it for emissions.
Tim Reese
Maine beekeeper's truck: '77 J10 LWB, 258/T15/D20/3.54 bone stock, low options (delete radio), PS/PDB, hubcaps.
Browless and proud: '82 J20 360/T18/NP208/3.73, Destination A/Ts, 7600 GVWR
Copper Polly: '75 CJ-6, 304/T15, PS, BFG KM2s, soft top
GTI without the badges: '95 VW Golf Sport 2000cc 2D
Dual Everything: '15 Chryco Jeep Cherokee KL Trailhawk, ECO Green
Blockchain the vote.

weeegoneeer
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Re: Keep air injection or not?

Post by weeegoneeer »

Sirrus - it's a bit loud for my taste.... It sounds good rumbling around town but an hour with a 3000RPM drone down the highway and turning the radio up so you can hear it, while yelling at your passenger to be heard isn't too fun!

It's a quality kit though, actually going to see if there's anything I can add to make it quieter (one of these days...)
1984 GW

letank
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Re: Keep air injection or not?

Post by letank »

sirrus wrote: Wed Sep 23, 2020 8:42 pm I was actually looking at BJs exhaust kit for some time now - how do you like it? Is it loud or moderate? I'm looking for something on a quieter side, buit I still want to know that I have V8 under the hood :)
I used to have the cherry bomb when I bought the 85, not obnoxious even for driving for long distances, then bought the better type at the zone for $50ish or so , a tad quieter. The 74 has the standard round type for that vintage, no cat, and it is almost silent...

Mufflers tend to be collateral damage when doing trail, inexpensive is OK for my trail use.
Michel
74 wag (349 Kmiles... parked, next step is a rust free body)
85 Gwag (229 Kmiles... the running test lab)

candymancan
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Re: Keep air injection or not?

Post by candymancan »

sirrus wrote: Mon Sep 21, 2020 9:22 pm So after more reading and thinking I’m leaning towards keeping air injection and getting two holes with broken bolts shut. Two points of air injection should be enough for the system to work

Next question is how to plug those holes - as I understand it welding cast iron is very tricky and can’t be done with manifold on the engine. Taking it off will definitely result in more broken bolts which will send me to the whole new world of struggle :) what I came up so far is to plug holes with high temp putty for exhaust repair and maybe wrap it over with exhaust repair tape so it won’t blow out. I know that’s not the best solution, but I tried tapping a threads in those holes to put a bolt in there and failed miserably. Any other suggestions?

You can weld cast iron easy. Torch it hot and weld it with a regular welder.

My injection tubes on the drivers side are welded shut by a previous owner. My guess they broke at one point. And the tubes that arent broken i put a pipe plug in with some rtv where the rubber air tube went. Worked great

Honestly what id do with your open ports. Is heat them with a torch till theyre close to red hot and fill the ports with weld. But thats just me.

Or you could get a bolt thick enough to self acrew itself in and lather it eith that muffler manifold weld putty thats good up to like 2000f.

I have a manifold exhaust leak and i used that manifold puddy you find in autozone and it hasnt broken or melted or burned off or leaked in 4 years.
Last edited by candymancan on Thu Sep 24, 2020 6:11 pm, edited 2 times in total.
1998 Jeep Grand Cherokee 5.9L Limited 219k
1998 Jeep Grand Cherokee 4.0 I6 laredo 430k
1990 Jeep Grand Wagoneer 155k
1976 Jeep J10.. 85k(repaired)

candymancan
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Joined: Tue Mar 22, 2016 11:32 pm

Re: Keep air injection or not?

Post by candymancan »

sirrus wrote: Wed Sep 23, 2020 8:42 pm
weeegoneeer wrote: Wed Sep 23, 2020 8:16 pm Sirrus - I need to pass Oregon DEQ as well - I have plugged air holes on my manifolds & the non-air injection cat sold on BJs with their stainless exhaust set — it's a magnaflow I believe and isn't too spendy. Pass DEQ with flying colors, no EGR, manifold vacuum (so more advanced than factory at idle). I think Air Injection had more to do with the catalyst technology back in the day. If it were me, I'd just plug them and get a modern cat. You don't need to maintain tubes and an airpump at that point.

Have never had an inspection in Multnomah County where they confirm original emissions equipment on the motor - they just want to make sure you have a cat with the floor mirror and that the stuff coming out of the tailpipe isn't toxic. Washington County may be harder but I doubt it. At the end of the day it does feel good to not be superpolluting, and be able to do it with modern stuff.
Thanks weeegoneeer! That sounds reassuring as I was hoping I can get away with modern cat and no air injection. That would simplify things under the hood a lot. Guess another order from BJs is coming up :) Now I have to find someone who needs new manifolds, bolts and reman air pump though

I was actually looking at BJs exhaust kit for some time now - how do you like it? Is it loud or moderate? I'm looking for something on a quieter side, buit I still want to know that I have V8 under the hood :)


I use a magnaflow cat, and a flowmaster super 44 muffler. It sounds perfect to me. It has that nice blub blub blubl blubl at idle. And it isnt loud to me on the road. I hear the tires and wind more than my exhaust at highway speeds.

But thats just me of course. I love the way my Jeep sounds. Loud are borla exhausts with headers and a cam You should hear the camaro we have itll make your ears ring.

But my waggy is deff louder than my 5.9 360 Zj with its stock exhaust


I can record a video if you want ?
1998 Jeep Grand Cherokee 5.9L Limited 219k
1998 Jeep Grand Cherokee 4.0 I6 laredo 430k
1990 Jeep Grand Wagoneer 155k
1976 Jeep J10.. 85k(repaired)

Topic author
sirrus
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Re: Keep air injection or not?

Post by sirrus »

I’m going to plug the holes with hood threads with plugs from BJs, and the other ones will get a bolt with some high temp putty at least as a temporary solution. Ideally I’d prefer them welded, but I can’t do that myself. And you know how temporary solutions tend to outlast permanent ones :)

Rest of exhaust is less priority, but I want to address it at some point. Two main issues I have now are annoying exhaust drone at 45-50 mph (it goes away at lower or higher speeds) and ticking sound from heat riser valve which is flopping around (spring is gone). I can get a new valve from amazon, but with rest of exhaust it’s tricky as what’s quiet to one person is too loud for another, and you won’t know until it’s installed and it’s too late to change anything. Maybe I’ll have to add resonator between a cat and muffler to get rid of drone once and for all.

Candymancan, that video would help if it’s not too much trouble!
Sometimes we reinvent the wheel not to have more wheels but to have more inventors

1988 Grand Wagoneer - AMC 360 with ProFlo4 MPFI, TF727, NP229 FOR SALE
2021 JLU Willys EcoDiesel - new shiny toy
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