A.I.R. system removal

[ClydesdaleKevin]

Outstanding!  I was just going to suggest the Doorman drain plug, part number  65231, 7/8-18...since that is what we'll be using when I tackle this project soon.  Glad it all worked out for you.  Good job!!!

Kev

[JerryP]

Theres a lso going to be a ton of vacuum lines to remove/reroute and your check engine light if equipped may stay on.

Unplug the wire on the left side of the air filter cover if the check engine light stays on.
This is addressed in one of the AIR threads

[JerryP]

Or just get a welder to weld the tube nuts closed. Might be a lot cheaper. It is best to weld them while they are installed though since they will change dimension due to heat and may not go back in if welded outside of the manifold. Although a good welder with a TIG unit and a heat sink could do it.

I welded mine.
happy with the results

[Rickf1985]

You may want to remove the nuts and take out the tubes from inside the manifolds first. They just slide in and are a substantial restriction to the exhaust. Less restriction equals better performance. Then you can put the nuts back in and weld them or use the Dorman plugs mentioned. I welded mine since I am too cheap to buy the plugs. W% Just be aware that the original setup has the flare of the tube mating with the flare of the tube inside the manifold so there is nothing for the nut to tighten against technically without the tubes. I left the tube flare in the nut and welded it in there. That said, mine do not leak, I just ran them all the way in till they stopped.

[Rover71]

I removed most of it a few years ago, but as it wasn't rusted out ,just left the manifold pipes installed. Plugged the two supply holes with short hoses & plastic pipe caps that fit.
Worked well since then- Serpentine belt I used is Nissan Altima 92-97--6PK1335 Metric or Goodyear 4060525. No guarantee it will work on other units though. Original configuration used 4 belts , 3 V and one ribbed, now eliminated one V that drove upper smog pump.
I hope this may be of some benefit..

[tmsnyder]

Can anyone CONFIRM that an M22x1.5 plug is what is needed to fill the threaded holes on the exhaust manifolds of a 1989 Chevy P30 454?  I can order 8 of them from the U.K. off ebay, but don't want to have to return them if they don't fit.  I've read every post I can find and have not been able to confirm this myself.  Since I work on Helga in my driveway on weekends, I want to have all the parts before I start tearing things down.  Subdivision frowns on people working on CARS in the driveway, much less giant RV's

This is an old post, but I just went through this.  Measured the threads and it was a very oddball thread.  It measured 22 mm but it had tpi threads!  Measured a perfect fit on one of thread gauges, I don't recall but it was something like 18 or 16 TPI (threads per inch).   I could not locate an appropriate plug, ended up just cutting the nuts off flush, pressing in a bit of 7/16" rod and welding the outside end closed. 


Also be sure to remove the air injectors from the ports and cut them off short before reinserting them.  Those things extend right into the exhaust port of the manifold, almost to the valve.   So imagine a 5/8 diameter circle in the center of a 2" port, it's blocking a lot of exhaust flow if you don't remove them or cut them back near flush with the inside of the manifold.

[ClydesdaleKevin]

Just a quick note on this thread, and a question.  First, the correct size is M22-1.50, and the Dorman part number I used for one of them (long story) is 65384.  I have 3 more on order from the local auto parts store to finish blocking off the driver's side...since the tubes failed from rust and toasted 2 of my spark plug wires and a nearby wiring harness...and my parking brake cable.  So I'll be removing the AIR system from the driver's side completely between now and Wednesday.

So here is my question:  Do I have to also do the passenger side to avoid any imbalance that might damage the engine, or is it okay to wait a while on that side?  I was planning on removing the system in Arizona as well as some more improvements, and was even thinking of going with Banks headers...so the extra work and expense of doing the passenger side as well would be something I would like to avoid for now...as long as it won't hurt anything.  The passenger side doesn't appear to be rusting and falling apart like the driver's side is.

Kev

[Rickf1985]

Won't hurt anything, makes no difference in engine power. just burns left over gas in the manifold. You were actually still using that system? You must have the most mileage on any operational A.I.R. system in an RV!

[ClydesdaleKevin]

Good to know!  Thanks Rick!

Kev

[tmsnyder]

Hi Kev,

I had those air tube fittings out and in my hand at a machine shop.  We measured it 6 ways to Sunday and it definitely wasn't 1.5, it was an exact match for a tpi gauge, but measured 22mm OD.  So an oddball size that GM made up for this application probably to prevent people ripping it off and plugging the hole with a standard size plug lol. 

That's not to say that a 22x1.5mm won't thread in for a bit before it feels like it get's tight.  It definitely would jam in there and plug up the hole almost completely. 

Making plugs from the old fittings by plugging with solid rod and welding it up on the end results in the correct thread on the plug.   The stock fittings seal the air tubes against the air injection fingers that are slipped through each port and inject the air very near the exhaust valve, so if you pull these out and cut them off so that they do not impede the exhaust gas flow at all (unlike stock which impedes the flow a lot), when you reassemble the fitting will seal against the factory finger seal for a leak-free solution.   Also, cheap if you have a welder and a hack saw. (free)

Just my $0.02 from my experience eliminating the air system from my 1989 454.

Todd

[Rickf1985]

Hi Kev,

That's not to say that a 22x1.5mm won't thread in for a bit before it feels like it get's tight.  It definitely would jam in there and plug up the hole almost completely. 

Todd

That's the idea of the whole thing, to plug the holes. The fittings are brass and the manifold is steel so if the threads are off by a tiny bit that is even better. It means they will conform and jam and completely seal the hole.

[tmsnyder]

I guess that's one way to do it LOL

[ClydesdaleKevin]

I got all four out today and the other three will be at the auto parts store tomorrow morning.  That said, the M22-1.50 threaded in about half way by hand and wasn't too hard to coax it in the rest of the way with a 3/8 inch drive...so good enough!  I coated the threads with JB Weld high temp red sealer, and will do the same to the other three in the morning.

Kev

[M & J]

Some pictures of what/how would be a plus Kev. Either here or on your blog post.

[tarifachris]

Great pics and info here...

Unfortunately i live in Phoenix AZ and i have to go to emission testing every year... I pass, but I have to
drive on the roller dynometer and they measure exhaust emission at idle and at 3000 RPM's.
What a bombastic sound at 3000 rpm under load in the little testing garage! They do as well an
visual check under the doghouse - they have manuals and pics for every year and what emission parts
has to be on your 454...

Sooo well, dream on to remove the emission crap...

[Rickf1985]

Even for an 88? I thought California was the only state that still went back that far.