MalMac 1,332 #1 Posted August 25, 2011 Ok I ask this question on another site which is one that every time you post someone has to ok it which draws the post out way too long. Anyway being a Wheel Horse guy and mainly a Kohler guy I am stumped as to what to do with this Briggs Vanguard 14hp OHV. It's on a Zero turn and was working just fine until it shut off. Just as if you turned the key off. I tried to restart it and all it would do is spin and no fire at all. I got it to finally start but could only keep it running at a low RPM by using the choke. Even that method gave out. Now what I am left with is the engine will start but die instantly. I have taken the top off the carb and cleaned as best I could with cleaner and a wire through all the jets etc. Took the fuel line off the carb to check the pump and it seemed to be putting out gas ok. It just seems that when it starts it runs out of gas like its emptying the bowl. I can try to start it again by turning it over until gas pumps up to fill the bowl. It fires dies and the whole process starts all over. The carb on this thing is almost Identical to the carb used on the onans. And if your a 520 owner you know how well that carb works! I am at a loss here. I probably going to have to take the carb totally off but wow you would not believe how much disassembly there is just to get the carb off. Anyway any ideas or thoughts would be appreciated. Share this post Link to post Share on other sites
Don1977 605 #2 Posted August 25, 2011 Sounds like a weak fuel pump to me. One other thing those carbs have what looks like a hose connection coming off the side of the carb. that is open to the air. If this gets stopped up it will not run. Share this post Link to post Share on other sites
kpinnc 14,661 #3 Posted August 25, 2011 My "worker" tractors get whatever it takes to make them run- including the wrong engine from time to time: This was a 1991 520-H that I used a Briggs Vanguard 14 on, and it's awesome. These engines are one of the few "newer" engines that actually have great power. This tractor can mow grass with a 48-inch mower deck that my 518-H struggles in with a smaller deck on it. It's a tough machine! I agree you may have issues with your fuel pump- but two other things to look at are the fuel solenoid at the carb, and the oil pressure switch at the filter. If the fuel solenoid does not open (the "click" you hear when you switch the ignition to run), then the engine will only run a couple seconds before starving itself for fuel. You can replace it, or get rid of it and replace it with a bolt of the same thread size. Your key switch can also cause problems with this as it becomes worn and makes poor contact in the "run" position, which provides 12VDC to the single wire on the solenoid. The oil pressure switch, located on the oil filter standoff, is a "normally closed" switch that opens when a minimum of 4psi is seen at the filter. The switch grounds both ignition "coils" at the flywheel until oil pressure reaches minimum safe pressure. With a meter, you should see a solid short to ground on the single terminal with the engine off, and an open with the engine running. You can disconnect it, but I would not run the engine long that way- just in case you actually have a problem with the oil pump. Good luck! :thumbs2: Share this post Link to post Share on other sites
MalMac 1,332 #4 Posted August 25, 2011 Ok guys thanks for the suggestions, I'll try today or tomorrow and let you know. I did check the fuel solenoid it seem to be working. Maybe a week pump? One thing I just thought of when I start it and it dies, if I would then take the top off the carb the bowl should be empty if its starving for fuel right? Share this post Link to post Share on other sites
