cgambino1018 28 #1 Posted June 10, 2020 newbie here, have a 1988-90 312-8 that sat for 2 years. tried to start it today.. while spraying starter fluid it would run. once i stopped the stream it would die. i got gas going to the gas pump but not out the other end. i took the pump off and this is what i see (see pics). what are my options? do i just order a new pump or try to fix this. seems like the gasket is torn. all help is appreciated. Chris from CT. 1 Share this post Link to post Share on other sites
Alex175 784 #2 Posted June 10, 2020 Top picture it appears as though your check valve is not in where it's supposed to be, it should be seated down in that indent on the top of the picture in the opposite direction of the check valve in the bottom of the picture. One is designed to let fuel in and not back towards your tank, and the other is for letting the fuel out towards the motor, but not back into the pump. I battled this issue myself the last few days, albeit on a slightly different brand pump so it's design was minimally different, but that would need to be reinstalled or the pump won't do anything. As for your mention of the gasket looking torn, if you are referring to your second picture, that is the fuel pump diaphragm, and if that is indeed torn it would have to be replaced as that, in conjunction with your two check valves, is what pumps the fuel. So the long and the short of it is, if there are no tears in the diaphragm and you can reinstall the check valve you should be fine. If the check valve cannot be reinstalled, or the diaphragm is torn, it might be best to get a new pump. Share this post Link to post Share on other sites
The Tuul Crib 7,339 #3 Posted June 10, 2020 If that is the plastic pump I wouldn't attempt to rebuild it. You might want to check into an electric fuel pump.They are a whole lot more dependable plus if the diaphragm breaks in the pump you have it could dump gas into the crank case. 3 1 Share this post Link to post Share on other sites
Bill D 2,248 #5 Posted June 10, 2020 Another option would be a modern vacuum impluse pump. These are found on most new machines and readily available. Brian Miller sells the necessary plate with a 1/4" barbed fitting and pump, or you can make your own. My neighbor has a GT 1142 with this style pump on it. It starts much better than my Kohler with a mechanical fuel pump after sitting all winter. Bill Share this post Link to post Share on other sites
gwest_ca-(File Mod) 11,483 #6 Posted June 10, 2020 5 hours ago, The Tuul Crib said: If that is the plastic pump I wouldn't attempt to rebuild it. You might want to check into an electric fuel pump.They are a whole lot more dependable plus if the diaphragm breaks in the pump you have it could dump gas into the crank case. Yes make sure you did not get gas into the crankcase. If the oil level has increased that is what happened. Garry Share this post Link to post Share on other sites
cgambino1018 28 #7 Posted June 11, 2020 i put everything back together based on the advice above and it started.. lets see how long this lasts.. wish me luck. Plan B but a new pump. Thanks for all the advice Share this post Link to post Share on other sites
