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Name that part...rather please help.

Goboysgo

Contributor
New Member
Joined
Jan 19, 2022
Messages
23
I've got a 72 with a 302 stock engine. A few small bits of emissions components I'm curious about, where or how they mount and the magic question of how the vacuum routing may like to go back to original configuration. The distributor is a dual vacuum.

The truck seems to run with the electrical component plugged in and not so much unplugged

I have yet to look into the charcoal can much, the large ribbed tubes were brittle and broken. (Replacements available? )

Pretty sure the air cleaner does.not have any small vacuum ports. Need to investigate when I'm up close and personal with the truck

Its ok please laugh at me

Thanks dudes
 

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Steve83

Bronco Guru
Joined
Jul 16, 2003
Messages
9,359
Loc.
Memphis, TN, USA, Earth, Milky Way
It's hard to assist with NO PICS of the engine bay, engine, carb, other components, wiring, connectors... To ID a connector, look up the wire colors on this page & the NEXT several:

(click this text)


Are you saying that the engine won't run with one or both of those components unplugged? Neither should affect how the engine runs.
 

DirtDonk

Contributor
Bronco Guru
Joined
Nov 3, 2003
Messages
51,618
Is yours a very late '72 by any chance?
The blue thingy in the middle of the first pic is a vacuum advance controller for a dual-diaphragm distributor. It was common from about '68 through '73 I think, but I could be wrong about the range of years. It mounted to the rear of the intake manifold behind the carb and had manifold vacuum connected from the "vacuum tree" (or rather just a small manifold on your engine) with a couple of different sized ports.
It's actually pretty simple plumbing, but I could never recall it from memory and always had to look it up. Wish I'd taken pics before instead!
If your current distributor is a single port vacuum advance, just leave all this other stuff off.

The single port thingy at the bottom of the first pic looks like a carburetor choke pull-off from a '73 or later carb.
And the item at the top I've seen plenty of, but could not tell you what it does. Reminds me of either a component from an "ambient switch" system, or an EGR controller.
Hence the questions about yours being a later build '72. Was yours the recent "P" code I saw not long ago?

Paul
 

syndicate1

Contributor
Sr. Member
Joined
Feb 14, 2015
Messages
460
I beleive emissions controls were factory installed beginning in '74 (CA models) and '75 or '76 nationwide.

Here are a few pics of my '74 engine bay with Emmisions and some vacuum diagrams to help you out.
 

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syndicate1

Contributor
Sr. Member
Joined
Feb 14, 2015
Messages
460
I beleive emissions controls were factory installed beginning in '74 (CA models) and '75 or '76 nationwide.

Here are a few pics of my '74 engine bay with Emmisions and some vacuum diagrams to help you out.

One more vacuum diagram...

3b6556fc65ec24d48eac7aa5f3fb5fc4.jpg



Sent from my iPhone using Tapatalk
 

DirtDonk

Contributor
Bronco Guru
Joined
Nov 3, 2003
Messages
51,618
Emissions control devices in general actually started in '66 with the air pump/thermactor setup. Skipped a year here and there after that, but it was there early.
The dual-diaphragm distributors were about '69 or so? The little blue devil thingy was from '70 until whenever. The big year, at least in CA was '73. That's when all sorts of stuff got unleashed on the engine compartments of Broncos. Carburetor changes, including electric chokes, and stuff like that came about in '73.
Each year after got even more goodies, so yeah, your '74 would have had even more fun stuff to work around and learn about. With '76 and '77 being really loaded.
But don't get started on '78's and '79's!

Paul
 
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