Gas pump shuts off repeatedly when gassing car
It is nothing to do with the canister or associated pipework.
There would be no problem if the filler pipe entered the tank at the highest point but mostly they don't. Realistically the problem is like filling an old-fashioned teapot through the spout if the lid was sealed down tight and there was no vent - once the level has risen to a point equivalent to the top of where the spout enters the teapot a pressure begins to build under the top that resists further filling.
To overcome this problem in the fuel tank and to allow complete filling, the high points have a vent and each vent is joined together by a hose that is terminated at a vent in the filler pipe at a height above the tank top.
When fuel blowback happens during filling the cause is mostly one or more of those vents or hoses is blocked or squashed or otherwise damaged...
Oct 07, 2017 |
2006 GMC Envoy