How do I (re-)connect the charcoal canister (EVAP system) on a 1981 4.9L? (WAS:Carb Tubing Question)
 

Hello:
This evening my truck died, going down the street, and was difficult to start and run. I managed to get it home...just up the street.
I found a vacuum hose disconected from my carb on my '81 F-100, six cylinder. I put it back on and now the truck starts and runs. This tube runs to a whitish box mounted just inside the grille, on the right side. This same tube has a smaller tube running off of it from a "T" 2-3 inches down from the carb. It is pretty long. I can not find the hole for this fitting to fit into. It is possible this fitting has not been hooked up for years, I really don't know. I drive my truck a few hundred miles a year.
Any guidance is much appreciated.
Thank-you for reply.

Pictures would be REALLY helpful here, I'm not familiar with any whitish boxes near the grille but I'm not familiar with a lot of stuff but maybe somebody else will recognize it if they see it.

Also, is this a California truck? Please click User CP in the top-left and finish filling out your profile so we can see where you're at.

Can you post pics of the whitish box?

That box sounds like the charcoal canister, with the line running from the carburetor bowl vent. I believe the line that tees off of it runs back to a gizmo near the PCV valve that controls the purging of the canister.

Thank-you all very much for the help.

Done.
Thank-you.

Well, I'm back with the dangling vacuum hose question. My truck still isn't acting right.

Thank-you for reply.

Here are some pictures.
The whitish box is inside the grill, near the radiator. The main tube, larger one of two together on top, runs from the carb to it. This is the tube that my connection T's off of, a few inches in front of the carb.
http://img109.imageshack.us/img109/3738/010ezs.jpg

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Here is the carb, with the tube, T-connection and disconnected end showing. It looks like the black nipple connection could be broken off.

http://img546.imageshack.us/img546/3693/001wlo.jpg

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Deleted.....

This is how the tube seems to want to hang, from the T. The connection end is out of sight.

http://img84.imageshack.us/img84/1294/008vit.jpg

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Any idea about where the disconnected black end should go?
Thank-you very much.

There should be a colorful diagram on your radiator core support that will explain where all your vacuum hoses should connect. But it can be hard to decipher at first.

The charcoal box, and all the connections coming off of it and to the carburetor is all part of the EVAP (evaporative) system. It routes fumes from your gas tank and carburetor fuel bowl to the charcoal box where they are stored and then back into your engine later for burning. That loose vacuum line should be hooked up somewhere, because right now you have a vacuum leak.

There should be a vacuum connection on the smaller, top fitting of your PCV valve, and there should be one attached to your carburetor (ported vacuum) someplace as well. I can see from your pics that there is vacuum port on the bottom of your carburetor with a piece of black vacuum hose broken off and stuck on the end of it. That black nipple connection might have connected to that hose. Check these places, and your vacuum diagram, and see if any of this helps.

Also, on your charcoal box, the single connection closest to the radiator, there is a hose that looks like it is going down. Where is that hose connected to?

Here is the vacuum diagram. You're right, I can't make sense of it. The hose I'm trying to connect comes off a T, from a larger hose connected to the carb. Can you deciper the diagram and help me find it's connection. The larger hose it comes off of connects to the box at the "front of the engine".

The absent connections on the carb have been vacant for years. And the hose I'm trying to connect is way too long for the inches needed to reach them.

The line that goes down from the charcoal box connects to another box just beneath it.

My PVC doesn't have a vacant connection.

Thank-you for helping.

http://img6.imageshack.us/img6/830/011wi.jpg

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Here she is:

http://img809.imageshack.us/img809/836/014gtd.jpg

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