Help identifying part

[jsbcats]

Newb question here I was looking under the air cleaner this past weekend planning some work I wanted to do to the engine and found this loose sitting on top of the intake. I've tried figuring out what it is with no luck. Please help a newb out

Wes

 

[jsbcats]

I found a picture that may help. In this picture I see the part mounted to a bolt on the valve cover.

 

[imusa76]

looks like a vacuum line switch.

its item #12 in this diagram

 

[jsbcats]

Thank you very much. Now on to why its disconnected and what its used for

looks like a vacuum line switch.

its item #12 in this diagram

 

[Bru]

That looks like a NOX switch. It was used to retard the vacuume spark advance here in Cali back in the early '70s. It was a law that you had to install it to pass smog till somebody took them to court and stopped it.

Bru

 

[72HCODE]

most likely it stopped working.

those switches usually have a bimetal heat sensor inside and after all these years it gets stuck either open or closed and causes problems.

you can just remove it.

http://www.7173mustangs.com/thread-under-the-hood-mysteries-distributor-vaccum-control-valve

in imusa76 photo of the vacuum system you can see that the #12 switch sits inbetween ported vacuum coming from the carburator and the DVCV switch, which went to the dual vaccum advance on the distributor.

what it did was keep the ignition timing retarded longer so the exhaust would run hotter(retarded engine timing) so that pollution emissions would be reduced from the tailpipe.

you can remove it and just hook up the ported carburetor line to the #3 the DVCV switch using hose #5

so remove hose #5 from #12 and hook it right into the ported carb hose connector..

you will have better function of the Vacuum advance on the distributor this way.

thus the reason your switch was disconnected and just left there was it was bypassed and took more time to just remove it. better to just leave it for the next owner as a piece of history as well.

 

[jsbcats]

Awesome. Thanks for the great info guys.