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LT gasping air

2K views 13 replies 6 participants last post by  Labman 
#1 ·
My '03 LT has just recently started gasping for air when I refuel?
Is this a sign of something I should be concerned about?
What, if anything, should I do to resolve the issue?
 
#2 ·
Sounds like the carbon canister. Do a search for how to remove it and I think this may solve your issue
 
#6 ·
Here's a quick way of checking whether the problem is your carbon canister. Locate the small black hose that exits under the saddlebag, probably on the right side.

Remove the gas cap and blow through the hose. Not kidding here. If the air you are blowing comes out of the gas tank filler opening (you'll hear it if it does) you don't have a canister problem.

If you are unable to blow anything through the hose, it's probably plugged. At that point you can either remove the canister as described elsewhere on this forum, or unplug the hose by squirting water through it.
 
#7 ·
Pardon my ig'nance, but are you refering to the single hose that comes out below the right bag by the back wheel? And are you saying that this is the canister "vent" line?
 
#9 ·
Labman - exactly correct. The problem that you are experiencing is that the fuel pump is pumping gas out of your tank, but there isn't any make-up air getting into the tank. A low pressure situation is being created. You hear a whoosh of air entering the tank when you remove the gas tank cap. Left uncorrected, the low pressure can create a vacuum which is strong enough to collapse the plastic fuel tank.

Make-up air enters through the hose beneath the right saddlebag, goes through a canister about the size of a mason jar located under the topcase, and then into the fuel tank. The cannister alos collects fumes from the tank and recycles them back.

The canister can become plugged as well, if you overfill the gas tank and fuel runs down the line inot the canister.

As a (cheap) first step, see if the rear hose is plugged.
 
#10 ·
Mike_H said:
Labman - exactly correct. The problem that you are experiencing is that the fuel pump is pumping gas out of your tank, but there isn't any make-up air getting into the tank. A low pressure situation is being created. You hear a whoosh of air entering the tank when you remove the gas tank cap. Left uncorrected, the low pressure can create a vacuum which is strong enough to collapse the plastic fuel tank.

Make-up air enters through the hose beneath the right saddlebag, goes through a canister about the size of a mason jar located under the topcase, and then into the fuel tank. The cannister alos collects fumes from the tank and recycles them back.

The canister can become plugged as well, if you overfill the gas tank and fuel runs down the line inot the canister.

As a (cheap) first step, see if the rear hose is plugged.
Is there a filter or anything to prevent dirt, bugs, etc, from entering that hose along with the air?
 
#12 ·
Yo Mike thanks for the extra info. You mentioned "clearing" it out with water. Should I think that this means in the reverse direction? Or by squriting water from the tank back to the canister?

Thanks,
 
#13 ·
Whatever works, just don't get water into the canister. I disconnected the line from the canister, injected water into the line and blew. That worked in my instance because the line was plugged. If your line isn't plugged, the canister is kaput and needs to be removed. Replacement is optional.

You can get to the canister by removing rear seat and the topcase. Both are very easy to do.
 
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