Help me identify these ports on my intake manifold

Help me identify these ports on my intake manifold

Flex BT

Senior Jeeper
Chesterfield, VA
1981 CJ7. I6, Weber 38/38 with TEAMRUSH upgrade. T5, Dana 300TC, Dana 30 / AMC 20, True trac w/ 4.10s. 33" All terrains

Blue and rust colored.
I didn't get any replies on my other thread:

So I thought I might at least be able to get some help identifying these ports on my intake manifold in a new thread. My jeep is reeking of gas and I'm about at my wits end.

There are things on my intake manifold and I don't know what they are. Can someone help me identify what these ports are and if they are possibly the source of the gas smell?

This picture is two raggedy looking ports on the left side of the manifold and I have no idea what they are


This second picture is sideways, I uploaded correctly rotated but I guess it doesn't like the dimensions or something. #1 I've gathered is the early fuel evaporation switch. How does this work and do I need to do anything with it? #2 is a port on the Weber 34 that didn't have anything going to it and I plugged and #3 was plugged by the PO. Should either of these be reconnected to the canister? All unused lines are plugged right now. Thanks in advance!

I believe the 1st is a temperature switch that is screwed into the water jacket of the intake manifold. #2 I would say was a manifold vacuum port, although I have no experience with the Webber. and #3 is the EGR valve, Exhaust gas recirculation, part of the emissions system and not a bad thing to have. I will let you research this one for details as it would take way more time than I have this morning to explain. In the first picture I would say the one on the right used to be a CT switch. It is a temperature activated valve that controls the vacuum to the emissions components and the thermostatic air cleaner. The other one I don't have a clue, specifically, but is taps the manifold hot water for what ever you want to do with it. Coffee warmer maybe??:laugh:
Do any of those have fuel vapor that might be coming out? The worst gas smell is after letting off of a hard acceleration.
Weber carbs must be Limited to 3-1/2 psi on the fuel inlet. anything over 3-1/2 will cause the float valve to remain open and pour raw fuel into the motor causing a very rich symptom. I have a Weber 38 on my 258 and run a Holley regulator and gauge just upstream from the carb inlet.

The fuel evaporation system isn't necessary in the summer months. There is an electric heater at the bottom of the manifold under the carb that is used for quick warmups. Cooling water is circulated in the jacket of the manifold to keep the fuel charge warm. I do not use either of them.

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I do have a Holley fuel pressure regulator installed and set to 3.5 PSI. Is the #1 temperature switch anything I need to be concerned about?

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