What am I looking at?

[Raider L]

@Turbo4whl, @K5ride,

Yeah, I see it in the diagram. It's a glorified EPA suction thingamajigger to keep unburnt fuel vapors from the air. And we sure wouldn't want any unspent fuel vapors, upon deceleration escaping into the air either, now would we? You have to know I have a deep dislike for anything coming from the EPA. That includes excess hoses, nickel size valves rerouting vacuum to some kind of catch can, triple screens, and filters, and any other kind of valve, or hose going to a thing that doesn't have anything to do with fuel economy or power, supposedly keeping us all healthy because of it, thus saith the most high government! I want them to stay out of my carburator and where or what my fuel goes or does.

Yeah @Kevin James, take that whatever it is off and when you go in for inspection put it back on. Deceive the government? You dang right! Move to Louisiana and you can drive your truck any way you want.

 

[shiftpro]

I'd hot wire it! Forget the switch!

You can run them both all the time. It's just cool to have the 'economy' mode. They sound rappy and tinny when lean, and then
when you fatten up it sounds like a totally different engine.
BTW, running propane lean doesn't burn up pistons, it just makes less power. MUCH less power.

 

[K5ride]

@Turbo4whl, @K5ride,

Yeah, I see it in the diagram. It's a glorified EPA suction thingamajigger to keep unburnt fuel vapors from the air. And we sure wouldn't want any unspent fuel vapors, upon deceleration escaping into the air either, now would we? You have to know I have a deep dislike for anything coming from the EPA. That includes excess hoses, nickel size valves rerouting vacuum to some kind of catch can, triple screens, and filters, and any other kind of valve, or hose going to a thing that doesn't have anything to do with fuel economy or power, supposedly keeping us all healthy because of it, thus saith the most high government! I want them to stay out of my carburator and where or what my fuel goes or does.

Yeah @Kevin James, take that whatever it is off and when you go in for inspection put it back on. Deceive the government? You dang right! Move to Louisiana and you can drive your truck any way you want.

I don't like the government getting involved with our lives either. That's why I bought a 1975 truck so it would be exempt from Calif smog inspections and I can do what I want with it. When I was younger and getting all my ASE certifications and differnt licenses for testing and emission related repairs, I kinda "fell" into this job. It was so easy and paid so well I ended up making it a career. I have to deal with the government ******** and regulations every day. I'll be retiring in a few years and moving out of California. They are the worst for needless rules and regulations.

 

[Kevin James]

I don't like the government getting involved with our lives either. That's why I bought a 1975 truck so it would be exempt from Calif smog inspections and I can do what I want with it. When I was younger and getting all my ASE certifications and differnt licenses for testing and emission related repairs, I kinda "fell" into this job. It was so easy and paid so well I ended up making it a career. I have to deal with the government ******** and regulations every day. I'll be retiring in a few years and moving out of California. They are the worst for needless rules and regulations.

I totally agree with you. The wife and I are getting ready to leave California as well and we have our hearts set on Tennessee.

 

[mtnmankev]

Is there going to be a quiz on any of this later ??

 

[Dale A]

It is factory and its a flame arrestor, that part for those who responded have it right. I believe why some trucks have this is because they were ordered up as commercial vehicles for things like forestry and firefighting in the trees/forest. They didn't want these trucks backfiring and blowing flames out the carburetors and catching grass and forest duff on fire. I personal owned an 85 C2500 crew cab that was a fire and rescue rig in southern California. It had a 350 with the same set up in it. this one also had a utility box on it that worked out great for my remodeling business.

Dale A

 

[Turbo4whl]

@mtnmankev

Is anyone keeping score? That may be a quiz question.

A decel valve has nothing to do with backfiring through the carb. It opens the throttle plate a little to let air flow into the engine and exhaust to burn the unburned fuel / rich mixture caused by the rapid throttle closure at higher rpms.

Just to be clear, the decel valve on these engines has everything to do about controlling backfiring.

This unit used in the early '80s does not open the throttle plate. Instead it is a spring loaded check valve that dumps air below the throttle plate when the manifold vacuum is at it's extreme high.

So if you decide to put fuel enriched charcoal (very flammable) inside the air filter housing, it might be wise to have it in a flame arrestor.