fuel tank selector
Laughing Gas
Joined: Jun 2016
Posts: 855
Likes: 56
From: Des Moines, Washington
Actually, you don’t want the line plugged. It should be open and connected to the charcoal canister unless you switch to a vented cap. What I’m thinking is someone plugged the line sometime in the past. There are those that think all emission related hardware is bad and should be removed. The evap system keeps unburned hydrocarbon out of the atmosphere without reducing performance.
Michael
Michael
Laughing Gas
Joined: Jan 2018
Posts: 898
Likes: 70
From: Coos Bay
Just a quick point. The caps do not freely interchange. The locking tangs on the vented system are further away from the cap vs the emissions equipped cap. Have used the emissions equipped tank with the breather line plugged with no problems, though common sense says it shouldn’t work. When you remove fluid from a cylinder, the volume must be replaced(with air) or the cylinder will cause a vacuum until the point that the walls crush. Hence the hissing from fuel cap. The fuel tanks vent through either the EVAP system or the fuel cap. If your EVAP tube is there and is not intentionally plugged, the rollover valve may have failed or the line has become plugged.
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Junior User
Joined: Apr 2019
Posts: 53
Likes: 0
From: Gilbert AZ
So I feel really stupid. Of course the vent needs to be open, you don't try and pour a gas can with vent closed and that is just gravity not suction. I took off the cap and it ran form over 7 mins so I am picking up a vented cap today. I was so focused in on the selector valve and the switch on the dash I couldn't see the big picture of how the system works.
Laughing Gas
Joined: Jan 2018
Posts: 898
Likes: 70
From: Coos Bay
Awesome. Take the truck to the parts house with you. Super glad you found a resolve. Weird its not working with the evap unplugged. I’d have recommended putting a chainsaw fuel filter on the evap to keep the dust out and allow it to breathe
Laughing Gas
Joined: Jun 2016
Posts: 855
Likes: 56
From: Des Moines, Washington
The fuel filter plugged into the hose is a good idea if you aren't going to restore the system and I may have mislead you when I said you may luck out and find a bolt in the hose. By that I meant that you could fix it pretty easily by removing the plug.
Michael
Michael
Lead Driver
Joined: Jul 2017
Posts: 9,601
Likes: 1,174
From: San Jose, CA
And I'm not sure if it was mentioned exactly or not Kerby, but that 4 minutes of run-time is normal for an engine that's just sitting there idling away in the driveway. And consistent with driving it is dying within seconds while you're driving. Especially under load. It just does not use all the fuel in the float bowl that fast at idle.
Sounds like you've got it, or are at least on the right path.
Good luck.
paul
Sounds like you've got it, or are at least on the right path.
Good luck.
paul
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