Help! Sheared Off AIR Pipe Retainer Nut

[YellowLark]

The AIR pipe rails for my '83 Riviera (5.0 engine) were badly rusted, so I wanted to replace them. They use hollow nuts where they attach into the cylinder heads.

Well, despite heating them with a torch, and soaking them for days with PB Blaster, I still managed to shear the heads off of two of them.

The two photos show (1) the cut-off nuts and inside piipes; and (2) how the AIR pipes fit within the hollow nuts. My problem now is that I can't get a grip on them with extractor bits because the pipes rotate within the shells of the retainer nuts. The pipes are flanged at the back of the nuts, so I can't figure out how to solve this challenge.

Since AIR pipes often rust, I expect that this must be a somewhat common dilemma. Any suggestions are much appreciated.

[rick60]

This could be a tough one! I would use a punch that has a slightly smaller diameter than the hollow nut to push the tube into the opening. Then I would use an extractor to remove the threaded portion. Don't compact the tube to the point it is impossible to remove. You also want to be careful not to damage the threads or seat portion of the head. Be sure to soak it with P Blaster. My method of removing these A.I.R. pipes is to first cut the pipe portion off flush with the nut using a large chisel. Then I use a 6 point socket to remove the hollow nut. Good luck!

[old-tank]

Using a thick flat washer weld the remaining stub to the 'hole' in the washer, then weld a nut to the washer.

Willie

[YellowLark]

Thanks for these suggestions.

Wow, the thought of trying to weld a washer to the hollow stub, which is now flush with the cylinder head, is beyond my skill level.

Well, I still have six cylinders I could try to use to get it to a machine shop. I hope that I will be able to make something else work before I have to resort to that.

[NTX5467]

ONE thing to remember about "extractors" . . . the inserted "bits" will have to get a bite on the inside of the item desired to be extracted. In so doing, they'll need to expand (or try to expand) the internal diameter of the object, which will put MORE force on the outer threads (which are already resistant to moving!!). THEREFORE, rather than the popular "extractor" route, you might be better off getting variety of drill bit sizes and progressively enlarging the internal diameter until they either can be removed or until you have an internal diameter large enough to get the flanged pipe out of . . . and the remains of the threads of the nut.

I'm not particularly sure about the Olds V-8s, but most of the engines I've seen have the AIR pipe installed into the exhaust manifold rather than the cylinder head per se. To do otherwise would have required a complete new head casting rather than something that could be added-on for the engines that needed it. It should not be a real problem to remove the exhasut manifold, but it might be best done by a mechanic unless you might desire to make it a project of sorts -- your judgment call.

Usually, the AIR pipes don't normally require replacement unless the one-way valves in the air supply line for each AIR pipe manifold start leaking and allow exhaust heat to move more into the pipes' air supply circuit. I've seen some held together by the thin layer of plating on them, which could then cause an underhood "heat" situation (sometimes melting the plastic AIR switching valve mechanism). So, be sure to put new check valves with the new pipes you install.

Just some thoughts . . .

NTX5467

[Guest 38cadillacjack]

ok don't know if this will work on this ,but i know it will solve most any frozen nut, bolt ,hinge, frozen tool,etc. been there, done that many times.heat the bolt or whatever,not red hot just hot enough to melt parrifin wax,put wax to item ,has to run aroud thread, pin what ever,ten try to turn,amazing ain;t it.i have picked up lots of tools that sat ruty for many years unusable 15 minutes later,could use again.heat can come from any sorce,that gets part hot enough to melt wax.this will probably work for the guy that posted today for screws in stainless.i;ve been tearing apart my 56 premiere for 3 days,used this several tmes.i keep a lb. on my bench.best of luck

[YellowLark]

Thanks for the great feedback.

The AIR passages appear to me to be into the heads, as shown in the attached illustration. The pipes were both rusted and also badly damaged by a previous owner who removed the other smog equipment. I am replacing everything from my parts car.

I wish that I had space to use a right-angle drill, but its just too tight. I do have space to use an extractor spanner.

Paraffin wax? Great idea that I will certainly try.

Now if I can just find the magic fix....