1973 Jeep Cj5 232 Vacuum Ports And Carb Port Problems

Hello all. Currently in the rebuild mode and need some help. I have a 73 with a 232. 1 bbl Carter stock carb. The majority of the vacuum lines have been plugged and pinched on the carb and manifold. No emissions control although it's not required here. I have looked through many diagrams, tsm, and the Haynes manual with nothing that looks like mine. I know I do not have a EGR valve and My pcv valve is connected as it should and has great suction. I'm replacing the valve, grommets, hose and oil filter with stock cap for good measure. I'm also adding a valve in the spot behind the oil filter cap now as it's plugged which I believe this would connect to the red circle. The blue, purple and yellow circles are a mystery but I assume they connect to the white circles which are pinched off steel tubes. Any assistance would be greatly appreciated I'm sure I may have something backwards. It starts and runs fine but it could be smoother. . Smells rich too

 

The white circles are the air injection ports in the exhaust manifold (Air Guard).

Red is likely a float bowl vent that connects to the vapor recovery system. Pretty sure '73 should not have this - I don't have a '73 TSM to check. I suspect you have a later model carburetor from what came with the Jeep.

Purple and blue are vacuum ports. Either could be manifold vacuum or ported vacuum, considering they come from the base of the carburetor. I would test them to see if they have vacuum at idle (manifold vacuum) or not (ported vacuum).

Yellow I don't know. I would look to see what the passage connects to - maybe it just goes into the air horn? That will give you a clue about what its purpose is. If it goes to the air horn, it's likely a source of filtered air for the choke stove (blocked off on this carburetor) ... though I thought the YF from this era did not use a filtered air inlet for the choke stove.

 

Thanks that's most helpful. For the red. Would you assume since the port sizes are differnt they should still connect? Given it could be a newer carb which is why they are different.

 

i agree with mr reese about the red circle; that's a bowl vent.

also, there should be a choke stove connection. (as pointed out by tgr). on my yf, that ran from a tube that was pressed into the exhaust manifold up to the choke, rather than to the yellow circle.

the pcv vent runs from the plugged hole on the valve cover to a fitting on the base of the air cleaner, allowing for filtered air. with the vent plugged, that engine probably leaks a bit of oil.

 

Thanks Wally. That tube is pinched off on the carb. Which is probably why I have a manual choke. 1 manifold port down.

 

Hi Jeff. The plugged hole behind your oil filler cap was for a formed rubber tube that connected to the side of the original breather cover. It also had a small filter in it inside the breather. Hope this makes sense.

 

i took a look at the YF that came with my jeep. it has the (yellow) port, as well as the (purple and blue) ports. really, it looks to have all the fittings yours does. it has been so long since it was installed, i cannot remember what connected to them, and i don't have photos.

another thing, the oil fill cap is not oem, and might have a breathable filter on it that replaces the pcv inlet filter, which is why the normal connection is plugged.