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Yikes.
Gas tank pressure problem
- Thread starter 77jimmy
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blueburban87
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This is an old thread but looking for ideas on this as well.
I running into extreme tank pressure build up after my canister flooded with fuel so I bypassed it temporarily to try and track it down. I ran the evap hose back into a T to the overflow tub ( closed loop system) I know this is not the correct fix and its not fixing the pressure building up. Cap still sizzles with pressure. if the evap line is bypassed what else could it be?
Its a new sending unit, walbro 255LPH pump running a blue print engine Holley EFI setup.
I running into extreme tank pressure build up after my canister flooded with fuel so I bypassed it temporarily to try and track it down. I ran the evap hose back into a T to the overflow tub ( closed loop system) I know this is not the correct fix and its not fixing the pressure building up. Cap still sizzles with pressure. if the evap line is bypassed what else could it be?
Its a new sending unit, walbro 255LPH pump running a blue print engine Holley EFI setup.
Ricko1966
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I'm not understanding where you've run your vent to. Pull the vent hose blow through the tube make sure it's clear to the tank. If it's clear,put a fuel filter in the vent hose for now it will allow the tank to vent,but will keep bugs and dirt out of the vent tube while you source a new evap cannister.
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75gmck25
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Go back to basics and check your sending unit and fuel pump fittings. The optimum solution for fuel flow and venting is a three port fuel pump (feed from tank, line to carburetor, return line back to tank), and a 3 port sending unit (feed to carburetor, return line in, vent line to canister), and a vapor canister under the hood.
If you threw your vapor canister and/or purge valve away in a moment of confusion, you can just zip tie or clamp the open rubber line up high on the radiator support and it will still vent.
The fuel feed and return lines should switch as you switch tanks, and the tank vent lines should be connected with a T and then run to the vapor canister.
If you threw your vapor canister and/or purge valve away in a moment of confusion, you can just zip tie or clamp the open rubber line up high on the radiator support and it will still vent.
The fuel feed and return lines should switch as you switch tanks, and the tank vent lines should be connected with a T and then run to the vapor canister.
