viperprime

So my son comes home from school today and says the 90 Firebird 5.0 TPI is making wierd sounds. I pop the hood and it sounds like an exhaust leak coming from the left side. I poke around and see that the threads on the AIR manifold where you screw on the check valve have snapped clean off.

It looks Like I'm going to have to replace the whole AIR tubes/manifold back to the exhaust manifold (& new check valve) I can't seem to find these parts anywhere. Who sells them?

2nd question: since I'm eventually going to have to replace both parts anyway would it be ok to use some JB epoxy putty as a temp fix to "Seal the leak?"

viperprime

UPDATE:
I've found and orderd the "tube" as they call it and a check valve from newgmparts
Anyone know if the outer nut that connect the two comes with either part?
My biggest fear is if I epoxy putty that together I'll lose the nut if neither of the new parts comes with it.

ASE doc

The epoxy couldn't hurt anything, though I don't expect it to hold up well in the exhaust. It seems like the AIR tubes would be something that Dorman would make. You might try asking anywhere that Dorman products are sold(NAPA). The same basic exhaust manifold was used on all V8 cars throughout the 80s and early 90s. If they don't list the part for your application, try another application and see if they have a picture that you can look at for comparison.

You say the flare nut actually broke right at the cast iron manifold? You may be able to drill the piece out and chase the threads. A 1/4 pipe brass plug will fit the hole once the threads are restored. The threads in the manifold are actually metric but the brass is soft and the size is close enough.

ASE doc

Do you mean the flare nut? The AIR tube will come complete with the flare nuts captured on the tubing and ready to thread into the manifold and connect to the check valve.

viperprime

No, Sorry, I looked closer and what i thought was a compression nut was just built onto the check valve so you can tighten it on to the manifold with a wrench. Looking at those flare nuts into the exhaust manifold, I suppose I should start the PB Blaster application process today to let it do it's thing.

ASE doc

PB Blaster and if you have it, a torch may be helpful. I've had mixed success with these. As they get older, they become less likely to come out without breaking. The last exhaust manifold I replaced on an 87 Monti Carlo SS, required a new AIR tube assembly as the old one broke coming off.