I have used rubber stopper at lest 4years but it didn’t fit properly so maybe it wasn’t sealed, I started in August having problems, I changed fuel filter , and it would be ok then in September, while pulling up t-post that were on incline tractor suddenly died, I assumed it needed fuel, but that didn’t work, I talked brother told him what I thought was bad fuel shut off, we replaced shut off then there was no volts going to shut off, replaced all fuses and that seemed to solve problems, but then in January it started again. So it seems it all stems from fuel tank and rubber stopper.