Removing Pop-off valve from air box on 1976 911

[91166 Carrera]

Does anybody have suggestions on how to remove the pop-off valve from the air box. The pop-off valve lid has either warped or the O-ring is no longer sealing and a vacuum leak is throwing off the AFR such that the engine hunts on cold start and then backfires after the idle stabilizes. Its at least 40+ years old. A smoke test has isolated the vacuum leak at the pop-off valve. I realize that without correcting the vacuum leak the AFR cannot be adjusted properly.

I've reviewed a number of posts here, and on-line, and haven't found any suggestions that specifically address this situation.

Any information on the subject would be helpful.

Harry
1976 Euro Carrera 3.0 targa (2023 Best of Show, IRPCA)
2024 Macan 4 EV

[75 911s]

The best thing to do is to buy a new airbox. There could be cracks in other spots and it's well worth it to just replace it imho.

[john walker's workshop]

Should be able to twist it out with a screwdriver.

[pmax]

The base is simply glued on, probably with epoxy.

And if you do get a new airbox, don't drill a gaping hole in it.

https://forums.pelicanparts.com/porsche-911-technical-forum/976754-pop-off-not-pop-off.html
https://forums.pelicanparts.com/porsche-911-technical-forum/689763-blown-airbox-replace-prevent-while-im-there.html#post6866364

[proporsche]

[QUOTE=pmax;12447477]There's no O-ring on the toilet seat.

The base is simply glued on, probably with epoxy.
.................................................. ...................

Yes there is an o ring ,look.

to Harry....
why don`t you just get o ring for it??

Ivan

[91166 Carrera]

Thanks for the comments everybody.

The POV sits on top of the airbox ribs, and the 40+ year old glue (epoxy) is yellow in color. I gave it a moderate-strength twist thinking it would just detach but no luck. I'll try more brute-strength, or try wrenching it out with a pair of channel-locks.

I really don't want to replace the air box if its not damaged. But I would consider replacing the plastic airbox for a stainless steel airbox. Where can I get one of those?

To John Walker, how would I remove the POV with a screwdriver?

To Proporsche, excellent suggestion of replacing the O-ring, maybe taking the O-ring from the new POV and placing it into the existing POV, then test it for a vacuum leak. That may be the first thing I do.

Harry

[proporsche]

[QUOTE=

To Proporsche, excellent suggestion of replacing the O-ring, maybe taking the O-ring from the new POV and placing it into the existing POV, then test it for a vacuum leak. That may be the first thing I do.

Harry[/QUOTE]
yup... very easy fix...

Ivan