Taking out smog,

brewter2

New member
I have a 304 v8 cj7, I would like to take out the smog pump and everything that is connected with smog, what can I take out and or plug off
 

Everything. why are you wanting to take it off? half of the stuff on mine were not hooked up or run to places they shouldn't have been, so I just took everything off because I didn't know exactly where it all went. If I remember, their was a return hose from the fuel filter that went to the charcoal canister, I ran that to the fuel tank as a return. The stock exhaust manifold had smog tubes on it, just cut and plug them, this was already done on mine when I got it. I never had any issues with the jeep with out the smog stuff on it, and we had to pass emissions tests back then.
 
In my experience, it has almost always been a bad idea to take off smog equipment. Since the 1980's, the smog controls have been engineered into the engine and ECM, and taking the controls off introduces complications, not to mention dirty air.
 
This is true on 82 and up cj,s with the 4cyl and 258. The 304 was no longer offered in the cj by that time and is non computer controlled. I would not do this on a 82 or newer, it WLL cause problems as mentioned.
 
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My 78 cj5 has the 304.
All of the extra stuff has been gone for a long time.
I only have 1 problem with mine. If it sits for a week, the gas evaporates from the carb.
I have to crank for 10 seconds before it starts.
There is a vent tube on my float bowl that needs to go to the canister.
So eventually I will plumb the tubes to the tank, at present they are rotted/disconnected.
Anyway, long story short, RIP IT ALL OFF....
 
EGR stops ping. Vapor cannister keeps you from losing raw vapor from the fuel tank. AIR pump and cat are conjoined. Get a non-aerobic aftermarket cat and the other stuff gets tossed.
 
I just got my canister plumbed back in.
You probably do want to keep the fumes under control.
Last week I had to replace my gas cap. I was loosing gas out the back, when the tank was full.
After putting a good cap on, the tank would build pressure, and had nowhere to go. I started smelling raw gas around the motor "all my rotted lines".
I ended up connecting the float bowl, gas tank vent, and crank case vent, to the air filter suction through the canister.
So far all my fumes have gone away. By the way, the fiber filter on bottom of the canister cost $ 2.50
 

I took everything but the catalytic converter off my 87. Just find a diagram from an older jeep that was not smog set up and change to that style set up.

Of course, make sure you can still pass safety inspections where you live or it will be hard to drive with cops pulling you over for no stickers.
 
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