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Hi everyone. I just picked up a 1977 CJ5 with s 232 and a one barrel. All the emissions was removed and the evap and EGR are still present. I have only had 4. Banger and v8 jeeps. There are 3 ports on the carb. Where do the vacuum lines hook up. I want to run the minimum amount, distributor, EGR, and charcoal canister. Any help will be great. Pictures even better, the emissions diagrams did not help since most of the parts are gone. 





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Scott21...Very cool and stock appearing AMC/Jeep CJ-5!  I don't have a FSM for '77 Jeep but can make a quick suggestion...Use a vacuum gauge and determine which port is manifold vacuum and which is the ported vacuum.

Manifold vacuum is continuous and strong pull, around 15-18 in/hg vacuum at an unloaded engine idle.  The ported vacuum port will have little or no vacuum with the throttle valve closed (at an idle).  As you tip-in the throttle, ported vacuum will spike high to provide maximum vacuum for the distributor.  The distributor canister needs ported vacuum.  Ported vacuum originates just above the throttle valve in the carburetor, and this relies on venturi vacuum, not engine/manifold vacuum.  Ported vacuum has been a time-honored source for the distributor vacuum advance and EGR.  EGR and the distributor vacuum canister each use ported vacuum.  

Each plastic port/pipe on the EVAP canister should be labeled.  Find out whether the canister requires manifold vacuum or PCV vacuum (manifold sourced) and if so, you can use manifold vacuum or the appropriate PCV sourced vacuum to that device.  

Caution:  EVAP vents the fuel tank and the carburetor's float bowl.  There is a purge line from the tank and one from the float bowl.  Is that the third pipe on your carburetor?  The bowl and tank vents are strictly for purging fumes, and you do not want a strong vacuum pull at these points...Find a vacuum diagram to confirm the safe routing of hoses for your '77 CJ Jeep and the 232 inline six...If you find a good diagram, please share it here with others.  Be sure of the correct hose routing to the EVAP canister, tank vent and float bowl vent: These are volatile gasoline fumes!  

I like to use a coolant temperature vacuum switching device (thermal vacuum switch or TVS) for the EGR, which is the factory method.  This will disable the EGR when the engine is cold and choke on.  It will allow the ported vacuum to pull at the EGR valve once the engine warms.  This is a simple switch to install at an engine cooling port, generally the thermostat housing or cylinder head,  or a coolant heat passage in the intake manifold.


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