Ok, I’ve searched and can’t find it, but I know I have read about it somewhere. On the gas tank for my ’78, it has three tubes coming out of it by the filler tube. Two of the three rubber/plastic caps are rotted. What was the purpose of even having these tubes, and where do I get replacement caps. I checked CCOT, and SOR, and I couldn’t find them.
Plastic/Rubber caps on gas tank
- Thread starter Jdmick
- Start date
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caps?
They should show up in the $OR catalog. Maybe cruiser Dan? Napa?
They should show up in the $OR catalog. Maybe cruiser Dan? Napa?
I don't know the correct answer - but as I have my tank out was wondering if any of the three can be capped?
I think at least two go to an expansion or other type of emissions device that is located above the gas fill door (which has the bolt over protection plate), and then maybe the other goes to the charcoal canister in the engine compartment?
Sure would like to be rid of these - not to hijack but is at least one or more needed for venting?
I think at least two go to an expansion or other type of emissions device that is located above the gas fill door (which has the bolt over protection plate), and then maybe the other goes to the charcoal canister in the engine compartment?
Sure would like to be rid of these - not to hijack but is at least one or more needed for venting?
I came across these as I tore my '75 apart. They go to a charcoal canister that's mounted near the heater motor on the firewall as part of some vapor recovery/emissions issue. I don't plan to hook mine up when I'm all done. I believe they can be plugged unless you're in a state where emissions might be a problem.
The three small lines coming off the tank (re: '78) should connect to a fuel separator (basically a vapor condenser) and then run to the charcoal canister. These act as both a vent for the gas tank and evap. containment. The larger line (approx 5/8") is a vent for the fuel filler neck to aid in filling your tank. Canadian models capped two of the three, I think, with one running thru a one-way check valve and then to the engine or wherever to act as an expansion vent.
Do not cap all three unless you have a gas cap that is vented to the outside. Most caps of the '78 era only allow air in to replace what you're using up in fuel volume. If the air in the tank should expand, say after a cold night and a hot day, you could pop a seam on the tank. Not fun.
Get rid of the canister and separator if you want but run one of the small lines thru a check valve (available at dealer/Specter) and then out of your passenger compartment. Or get a vented gas cap. I've heard of guys drilling a very small hole in their fuel fill neck outside the passenger compartment. You will smell fumes when outside the vehicle in that area, though.
Do not cap all three unless you have a gas cap that is vented to the outside. Most caps of the '78 era only allow air in to replace what you're using up in fuel volume. If the air in the tank should expand, say after a cold night and a hot day, you could pop a seam on the tank. Not fun.
Get rid of the canister and separator if you want but run one of the small lines thru a check valve (available at dealer/Specter) and then out of your passenger compartment. Or get a vented gas cap. I've heard of guys drilling a very small hole in their fuel fill neck outside the passenger compartment. You will smell fumes when outside the vehicle in that area, though.
