Fuel evaporator question (1 Viewer)

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wngrog

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I have a 1984 that I installed Wagon Gear panels into 7 years ago.

You have to relocate this evaporator thing to make the panels work.

I followed the directions and extended the hoses and moved this thing back to the tail light cavity.

It has always smelled like gas in my truck since I did this.

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(I pulled it out for a photo)

Why do I need this thing? I would love to just cap this whole thing off. I'm sick of the smell.

My truck is desmoged. Tank was replaced under warranty.
 
If you want the charcoal canister and all the tank vent plumbing to fill up with liquid fuel and have liquid gasoline burping & periodically gushing out through wherever the tank is being vented (usually the charcoal canister)... go ahead and remove the separator in the back of the car.

The separator is not an emissions component, but a fuel expansion and vapor separation device. It's required when filling the tank full to prevent the above. Not so much when the tank is less than 3/4 full.
 
Check your hard lines that run through the sheetmetal. If one is rotted or cracked could cause the issue.

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Thanks. That's what I was thinking I was told at some point.

I'll check those hard lines. That stuff really looked good at a glance.

I've got to get in there and seal the filler neck to body Gap that's allowing my fender to fill up with mud and water.
 
You can remove it but you will wish you didn't when you get 2 gallons of gas that shoot out the filler when you open it on unlevel ground. Plus your not allowing for expansion and contraction and it will eventually crack your tank or pop the spot welds in the baffles and cause you an even bigger problem.

Extending lines shouldn't cause a leak. Extending the lines and snapping or cracking one of the nipples on the separator will.
 
Great info. I need to dig deeper then. I must have pulled one of the hardlines and cracked it

None of the 4" of dirt I removed from the lower fender smelled like gas so no active leaks. Just fumes.
 
Swap the Tank and Purge hose on the charcoal canister to depressurize the tank to allow it to vent freely through the cc.

When the cc check valve sticks, the vapor pressure in the tank gets way high and the fumes exit at the point of least resistance. Which can be at any of the many vapor connection junctions at the rear of the car.
 
Check the routing of the hoses from the bottom of the separator. Make sure there are no "Dips" that will trap fuel. They should be routed to allow any fuel to flow back into the tank.

You might also check the metal vapor lines underneath to make sure they are still intact.
 
So I'm having the same issue...
I still have the gas odor in the cab. I even did the $22 gas filler cap mod and still notice the gas smell not as strong as before but still very noticeable. The other day I saw gas residue just under the fuel door. Now diving into the lines and CC...

I would think our gas tanks have no splash guards or chambers to keep it from sloshing up out of the filler neck.
Has anyone ever thought on running those fuel cell foams to help prevent sloshing...
 
The problem isn't sloshing. These trucks (and gas tanks) were designed to drive on rough dirt roads their whole life. The tank has internal baffles (or at least it did when it was new).

If the tank isn't venting properly and it's full of gas, gas will find a way out.

Be sure to never fill the tank to the brim. That warning is in the owner's manual.
 
Check the hard line that goes to the charcoal canister. I forget which one it is in the pic Reevesci posted. Follow it back from the charcoal can. Mine was plugged up and causing pressure in the tank and fuel smell inside. I was able to clear it by spraying WD40 in it from both ends, letting it soak in, applying compressed air- repeating till air went though it.
 
Swap the Tank and Purge hose on the charcoal canister to depressurize the tank to allow it to vent freely through the cc.

When the cc check valve sticks, the vapor pressure in the tank gets way high and the fumes exit at the point of least resistance. Which can be at any of the many vapor connection junctions at the rear of the car.

This is the top two hoses right?
 
Unfortunately the gasket where it meets the body is not and the lower fender is full of damp mud :(

Remove any rubber plugs in the bottom of the rear fender and leave them out forever. Flush out the mud with water, let it dry, then grease the lower fender cavity with spray Lithium grease (sold for lubing door hinges and hood latches). This way, it won't rust, and future water can get out.
 

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