PO removed Charcoal Canister and gas smell is overwhelming - advice or help? (1 Viewer)

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Joined
Mar 27, 2003
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Location
North Georgia, USA
Ok - first , I am a novice and am learning my way around. So, please be patient

Bought a 78 with a 75 engine.
PO de-smogged it he also removed the charcoal canister..and the PO ripped out a lot of stuff

When the pig sits and drives the gas fumes are almost overwhelming

I dug into it and the hose at the top of the fuel separator (which I believe should go to the CC) was cut and just hangs underneath body. See pics

Inside the engine, no visible hoses for venting I can see

I do see two fuel lines one with a filter and one without that merge into one before the carb

I’ve searched many of the mud posts and I’m just still confused how to reinstall the canister With my situation. ...or should I just bring it to a mechanic (may be easier) . Even if I got a CC, I’m not sure how to hook it up since most of the smog stuff was removed by the PO.

Here are some pics

Like I mentioned above the gas smell in the engine bay and inside while driving makes eyes water sometimes so I need to get this fixed ASAP.

Help/advice would be greatly appreciated

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It’s not that difficult. The tank should have a line which goes to the charcoal canister. Most people have bought aftermarket delco units (vc120) but there a variety of options. Then there are two other lines. A breather line which vents to atmosphere and another which connects to a purge valve that is connected to vacuum. Should be able to search purge valve.

check this thread
 
**i need a little more help please**

Based on hours of Searching
And reading posts etc. I believe
This is how I have to set up my Charcoal Canister which was removed By PO with all other evap items .

***I have a 1978 frame/body with a 1975 engine. Totally de-smogged ...nothing is left from the PO***

What I believe the steps are for me to add a
Charcoal canister to help with the fuel smell:

Step A). Connect the top one hose from the tank fuel vapor separator (3 tubes to one next to pass seat) To a check valve (I don’t know where to get this valve..anyone have a part number?)

Step B). Connect the fuel vapor hose from the check valve mentioned in “Step A” to the port #1 (To tank) on the charcoal canister (Duralast vapor canister VC120)

Step C). Connect port #2 on the Duralast charcoal canister to a “vapor canister purge valve AC Delco 214-552” 1>2 ports

Step C-1). Connect one of the ac delco purge valve Ports to a New “T” junction from the distributor vacuum hose.

Step C-2). Connect the second port to the carb. But where on the carb?...I’m still trying to figure this out..(I think this sucks excess vapor out of the carb and into the charcoal canister) . Anyone know?

Step D). Connect port #3 (purge) to the stock air Cleaner post air filter. (This dumps the cleaned vapors back into the carb/engine to burn)

**so I’m still a little hazy on “steps C 1 & 2” above since I don’t have many of the stock valves And hoses left from the PO ripping them out. None of the diagrams that prior threads posted are correct for my setup. it would be cool if someone Could clarify it for me.

Also, what type of check valve for the fuel tank vapor does everyone use and
Do I need special hoses from the fuel tank vapor to the charcoal canister?

Thanks all.
 
**i need a little more help please**

Based on hours of Searching
And reading posts etc. I believe
This is how I have to set up my Charcoal Canister which was removed By PO with all other evap items .

***I have a 1978 frame/body with a 1975 engine. Totally de-smogged ...nothing is left from the PO***

What I believe the steps are for me to add a
Charcoal canister to help with the fuel smell:

Step A). Connect the top one hose from the tank fuel vapor separator (3 tubes to one next to pass seat) To a check valve (I don’t know where to get this valve..anyone have a part number?)

Step B). Connect the fuel vapor hose from the check valve mentioned in “Step A” to the port #1 (To tank) on the charcoal canister (Duralast vapor canister VC120)

Step C). Connect port #2 on the Duralast charcoal canister to a “vapor canister purge valve AC Delco 214-552” 1>2 ports

Step C-1). Connect one of the ac delco purge valve Ports to a New “T” junction from the distributor vacuum hose.

Step C-2). Connect the second port to the carb. But where on the carb?...I’m still trying to figure this out..(I think this sucks excess vapor out of the carb and into the charcoal canister) . Anyone know?

Step D). Connect port #3 (purge) to the stock air Cleaner post air filter. (This dumps the cleaned vapors back into the carb/engine to burn)

**so I’m still a little hazy on “steps C 1 & 2” above since I don’t have many of the stock valves And hoses left from the PO ripping them out. None of the diagrams that prior threads posted are correct for my setup. it would be cool if someone Could clarify it for me.

Also, what type of check valve for the fuel tank vapor does everyone use and
Do I need special hoses from the fuel tank vapor to the charcoal canister?

Thanks all.


I Offer the Correct Updated OEM White Fuel separator Check Valves ..........

Send Me a PM ........
to discuss further , if your missing this part in your set up , you NEED it correctly installed right away ..........

thanks
matt



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I Offer the Correct Updated OEM White Fuel separator Check Valves ..........

Send Me a PM ........
to discuss further , if your missing this part in your set up , you NEED it correctly installed right away ..........

thanks
matt


Hey matt
Thanks
I hooked up my new CC setup and it works great. I did order an oem fuel vapor check valve from cruiser parts. If that part ends up being a dog ..I’ll PM you.
 
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First thing to check when you are smelling fuel fumes is--is the fuel tank intact? Are you sure the tank is not corroded and 'weeping" fuel and thus the fumes, into the cabin?
Had the same symptoms on my 77--turned out the tank was so rusted it "weeped' fuel out and caused the whole cabin to be fummed out--there were no drips apparent under the truck. Once I pulled the tank and inspected, the bottom looked like a pin cushion--covered up with the rust
 
First thing to check when you are smelling fuel fumes is--is the fuel tank intact? Are you sure the tank is not corroded and 'weeping" fuel and thus the fumes, into the cabin?
Had the same symptoms on my 77--turned out the tank was so rusted it "weeped' fuel out and caused the whole cabin to be fummed out--there were no drips apparent under the truck. Once I pulled the tank and inspected, the bottom looked like a pin cushion--covered up with the rust


Thanks for heads up . Tank is good . It is not the orig and was replaced a few years ago. Some of the lines coming out are a little
Crusty ...prob will change those out too
 
Search around and see if you can find a copy of the emisions control repair manual. From a copy of the '81 that I found a link to in another thread:
evap.JPG


Check the fuel tank, make sure everything is connected properly and everything is either connected to a hose going somewhere or well blocked (maybe there is a return line that should be plugged if not used, but the rest should probably be plumbed to something).

I'm not sure how the vapor separator is supposed to the mounted or how it was originally mounted. But, it seems intuitive to me that it should be above the fuel tank (use gravity to prevent fuel from getting into it?).

I pulled my tank out a couple months ago to fix the gauge sender and check condition of the tub underneath, and found the PO run the top of the vapor separator back to the fuel return (had not return line from my carburetor). I ran this back to the charcoal canister, and ran the tank's return connection up the line toward the fuel pump and then plugged it there (preperation for maybe getting a sniper EFI kit). Constant irritating fuel smell that's been inside my FJ40 since I bought it 5 years ago is mostly gone now....

(my charcoal canister is vented to the environment via a tube that runs into one of the voids in the body reinforcement.)
 
Thanks
Diagram helps

I added a canister and Plumbed or replaced all the vacuum lines.

No fuel smell! I won for now

I did notice my fuel lines prob need to be replaced soon , but that will be a project for another day!
 
Sounds like you got it figured out. On the Delco purge valve, little line goes to the distributor advance vacuum line or some other vacuum advance port that only has vacuum when not idling. The large ports on that valve, one goes to the purge port of the charcoal canister and the other needs to go to the intake manifold, preferably near the carb. The PCV port can be teed into for this purpose.

On the fuel separator in the cab, the three lines to the tank assure venting no matter the orientation of the tank since there is no breather/headspace dome on the top of a 40 tank. The little tank lets liquid condense out and go back to the tank. The top line goes as you have it, through the checkvalve and to the inlet of the canister. From the factory that checkvalve is located inside by the separator. Protects it from the elements, they do crack. A hard line then extended down through the tub and forward to the area below the heater blower. Canister was mounted to the fender behind the battery area. Another hardline crossed the top of the firewall to drivers fender area.

The function of the system is not only to trap vapors but to also vent the tank with air as the liquid is used. The fuel cap should be a sealing type to further eleminate possible fumes. The purge system was more sophisticated from the factory, as it had one extra step, either the computer, or a temperature sensitive vacuum valve read coolant temp and waited to purge the stored vapors into the engine after it had reached operating temp. It also only allowed purge at throttle positions above idle, as the excess fumes will throw off the idle settings. By using ported vacuum you assure it only purges off idle when the carb plates have been opened.

I am running the same settup and it has been working great for years, only difference is I found a period correct FJ40 canister for mine.
 
@REDDER1 , there's a lot of good feedback on this thread already. I would only try to add a couple of useful bits. If your 75 engine still has the original Aisin carb (or equivalent), and the original thermostat housing, then you lack a couple of systems that @kerplunk is showing on that 1/79 and later emission sketch. You won't have a carb float bowl vent, so no connection to the charcoal canister there. And I don't believe that 75 had the Bimetallic Vacuum Switching Valves (BVSV's) yet. Those came later. So your purge from the CC to the intake wouldn't go through a BVSV. Now, if any of your original 78 systems are intact (such as carb or thermostat housing), then you would have both of those features that I just described, so you will have to plumb together a hybrid of the two years. HTH
 

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