Help - Need to know where this goes

[Alan Lindquist]

This is a photo of the tank vent system for a 1980 SC. I had soaked/weeping hoses and all sorts of fumes in the cabin. I replaced the hoses (several hose clamps missing in this photo).

The smaller hose that snakes below the tank filler tube and under the fuse block goes into the fender wall. When I look for the exit on the other side, it seems to go into a "grayish" tank behind the headlight. Is that so?

I'm thinking that the vapors or over-fill or splash from a full tank go into the canister and get relieved into this tank?

Who knows what is really going on here? Is there a better way to vent fumes and overflow than the stock system?

Thanks for considering and replying.

[ossiblue]

Originally Posted by Alan Lindquist

This is a photo of the tank vent system for a 1980 SC. I had soaked/weeping hoses and all sorts of fumes in the cabin. I replaced the hoses (several hose clamps missing in this photo).

The smaller hose that snakes below the tank filler tube and under the fuse block goes into the fender wall. When I look for the exit on the other side, it seems to go into a "grayish" tank behind the headlight. Is that so?

I'm thinking that the vapors or over-fill or splash from a full tank go into the canister and get relieved into this tank?

Who knows what is really going on here? Is there a better way to vent fumes and overflow than the stock system?

Thanks for considering and replying.

You are correct in your assumption that the smaller hose and vapor/overfill go into the "grayish" tank behind the headlight. However, there should be a hose that exits that tank which then leads to the charcoal canister from which the fumes are then purged by engine generated air pressure into the intake manifold. I'm not sure where the canister is on your car--either in the engine compartment between the engine and firewall, or in the left rear wheel well. Check to see if it's still there and the hoses are connected.

Is there a better way? Possibly, but this system does work if all components are intact.

[Alan Lindquist]

Thanks. Yeah - the canister is back there in the engine compartment. That's a long way to go for a hose - front to back. I'll have to investigate the condition and connection of that hose.

[ossiblue]

Originally Posted by Alan Lindquist

Thanks. Yeah - the canister is back there in the engine compartment. That's a long way to go for a hose - front to back. I'll have to investigate the condition and connection of that hose.

The hose from the front tank (behind the headlight) to the engine compartment typically runs from a nipple inside the front left fender, down behind the gas tank, and connects to a metal tube inside the tunnel. At the rear of the tunnel, another hose is connected that feeds up into the engine compartment. You may have to do a little "getting under there" to see if the hose connections at each end of the tunnel are secure. As far as the engine compartment goes, a flashlight and mirror will probably be all you need.

[Peter Zimmermann]

OK, Let me try to explain this from memory with the caveat that I think the system changed for 1980 models.

The plastic tank has three hose nipples, two at the forward end, one at the rear. A hose should connect from the single, rear nipple on the car's gas filler inlet pipe near the gas cap (but inside the trunk).

The two nipples next to each other are different sizes, and a hose should connect the nipple on the gasoline tank to the larger nipple on the small plastic tank. WARNING, the hoses must be an exact fit, or fuel vapors might escape (clamps might not help if the hoses are the wrong size).

That leaves one nipple on the forward end of the plastic tank. A hose should come off that nipple, curve under the gasoline tank's filler pipe, and find it's way to a welded pipe fitting behind the fuse box. To find that connection it's probably best to disconnect the battery ground strap, then remove the fuse box screws and tilt the fuse box (leave all wires, fuses, and relays intact) away from the inner fender. You should be able to see a hose connection point, maybe even with an old piece of hose still connected. That hose will take your vapors out of the trunk and into the expansion chamber under the fender, above the w/washer reservoir.

Once you complete that connection behind/under the fuse box, you will have to jack up the car and verify that the hoses are connected properly at the expansion tank under the fender.