Check flywheel key. Sounds like it might have sheared. Also, check breather hole in gas cap. Might find it is plugged by dirt or a mud wasp egg! Do this first! When you put the machine away last spring, a mud wasp may have laid an egg in that little breather hole, and now it is blocked by the remains of that. Don't laugh--i've made some significant cash from that problem.

This is my first time on here, so I don't exactly know how to post so here goes. My JD-425 has a flooding problem. Sometimes it runs ok, and sometimes not. When I turn on the ignition, the fuel pump starts (as normal) and I can usually start it. Then, after running for a while, it begins flooding. This is between 15 minutes and half an hour most of the time. I can keep it running if I go full throttle and have the tractor under load, like mowing grass, but there is so much gas entering the carb that there is a bit of black smoke as well. If I stop it and remove the air cleaner, and look into the carb, there is gas everywhere. Here is what I did so far... The carb was new 3 years ago. But I removed it, and took it apart (did this 3 times). Each time I took it apart and put it back together, I know I did it right because the machine started and ran as noted above. I thought it just might be plugged or something. The first time I took it apart I also replaced the electric solenoid valve, just to be sure. And I know it works, because I saw it operating with the carb disassembled. Then, I thought it might be that the float valve was leaking or perhaps the floats had a hole and was full of gas. All was good. When the carb was back together, I blew into the fuel hose when the carb was full of gas and proved that the float valve was working. Hmmm. There is a manual in-line fuel shutoff valve, so what I did was throttle it back so that it would take 30 seconds to to let about an ounce of fuel out. Full blast, the pump actually pumps a lot of fuel. This time, I was able to keep the machine from flooding too bad. And was able to mow the 1 acre of grass I have. Today, however was different. It ran for about 5 minutes, then began to act up. I turned it off, removed the air cleaner and looked into the carb. When I turn the ignition switch on, (not engaging the starter) I can see tons of gas coming out of every carb orifice, flooding into the engine gas everywhere. This is without the engine running. The only thing I can come up with is that the fuel pump for some unknown reason has too much pressure behind it. Another wierd thing is that when I turn a sharp corner, under the flooding condition, the flooding gets noticably worse. Any ideas anyone? Is there a pressure regulator somewhere in the fuel pump line? Thanks.

Your gadget is the "anti-afterfire solenoid". Its function is to stop the flow of fuel into the MAIN jet of the carb the moment you turn off the key switch (when you are stopping the engine). Lest any reader get the impression that the small washers were not in their correct positions (prior to your removing the bowl) and that placing them into their rightful positions corrected the problem...............no. If the washers had not been in the correct places already, the defective condition would have been "fuel leaking from carb bowl". I would venture to guess that in your/this case, the "rough idle" was caused by water having segregated out of the fuel (stratification) and formed a layer or glob of water on the bottom of the bowl. This layer of water may "stir up" when the engine is started. The small droplets of water that arise from the stirring of the bigger blob can be drawn into the very small passages that comprise the IDLE or PILOT jet of the carb, effectively blocking fuel flow through them or at least causing the fuel to flow erratically. Small water droplets typically has little or no effect on fuel deliver through the larger MAIN jet. Water in the fuel supply (before you put the fuel in the tank) can cause fuel starvation issues if enough water collects in the gas filter that it forms a film of water to coat the filter media, obstructing the flow of fuel through the media. Water formation or segregation in fuel system components will continue to be a scourge due to ethanol blended into today's gasoline. Ethanol just "loves water" and will absorb water vapor right out of the atmosphere. This begins to take place inside the underground storage tanks at your local gas station and continues even after you pour it into your OPE fuel tank.

Well, you had to ask. To fully grasp the concept, one needs to have an understanding of basic electrical principles. Typically, the water hose analogy is used to demonstrate the basic principles. The supply water plumbing of a house is thought of as a battery. The hydrant valve would be a switch. The garden hose would be the conductor (battery cables) carrying water (current) to a sprinkler head (starter). The standing water pressure of the house plumbing (in PSI) is analogous to "battery power" (measured as voltage). In this comparison, opening the hydrant valve allows water to flow through the hose to the sprinkler, causing it to spin. In an automotive setting, operating the solenoid allows electrical current to flow through the battery cables to the starter, causing it to spin. Various factors affect the performance of an electrical circuit much the same as variables in plumbing will affect the spinning sprinkler. If you reduce the PSI of the house water supply, you expect the sprinkler to spin more slowly, similarly a reduction of battery voltage will result in a slower spinning starter. If you change from a 3/4" diameter hose to a 3/8" diameter hose, the sprinkler will spin slower. If you change from the OEM battery cable size to some wires half their size, the battery will spin slower. If you change the sprinkler out for one that is hard to turn, it will spin slower than the sprinkler that is free to spin. The same goes for a starter which is sticky or binding. The analogies described are very similar except that in electrical systems you will not be able to make changes or affect the components without suffering some serious consequences (to the components). The term "Amperes" is a tag used in describing the electrical flow (current) of an electrical circuit.. A battery does not "deliver" amps to the starter as though it were offering something "unsolicited". It is more like the starter is DEMANDING the battery give it the power it needs to turn the engine. So the starter is really at the mercy of the battery as to what it receives. Batteries are rated by their capability to furnish power described as "X number of Amps". But that rating is only true if the battery has a full charge and the battery is new. The analogy between water pressure and voltage is pretty accurate. In plumbing, pressure of a specific value will push a specific volume of water through a specific diameter conduit having a specific value of resistance to flow. In electrical systems, a specific voltage value will push a specific volume of electrical current through specific size conductors where there is a specific electrical resistance. The consequence to be faced in electrical systems where the "specifics" become "imbalanced on the low side" is heat production. It requires adequate voltage to push sufficient amps (in response to current draw) through a conducting circuit resulting in normal operation of the circuit components as it was designed for. Consequence of low voltage: If you cut the voltage in half but leave the other factors the same...........the result will be heat production due to the voltage not being adequate to push those amps through the resisting component. Consequence of insufficient amp capacity of battery: This is what we face when we are dealing with an old battery (anything that is not brand new). Amp capacity of a battery is relevant to its physical size (plate surface area) and the state or condition of the battery. Imagine two 12 volt batteries. One of the batteries fits a yard tractor, the other fits a large diesel engine agriculture tractor. Both have a voltage level of 12, but the amp capacities are vastly different between the two. The starters of each of those tractors is matched to the amp capacity of the batteries (and vice versa). Basically and fundamentally speaking, battery amp capacity is chosen for an application with the goal of keeping VOLTAGE DROP to a minimum when the starter load is connected to the battery. If you connect the yard tractor starter to the yard tractor battery you can expect perhaps a 3 to 4 volt drop in battery voltage after the starter begins spinning the engine, and that is acceptable. If.....you connect the yard tractor battery to the agriculture tractor battery, you might possibly observe a battery voltage drop of .3 to .4. But...........if you connect the starter of the big tractor to the yard tractor battery you could realistically expect the battery voltage to drop to zero. You can also expect the yard tractor battery to explode because that kind of load would be the same as connecting a battery cable between the posts of the small battery........in essence "a dead short". The explosion is the result of the voltage drop causing catastrophic heat build up and flash melting of the plates inside the battery case creating a steam explosion as the electrolyte vaporizes.............combined with ignition of the explosive battery gasses. Now back to the job of trimming a lawn. When a battery is "old", its amp capacity is less than when new, and so will not be able to meet the current draw requirements of the starter when asked to. This will cause the battery voltage to drop, further reducing the ability of the battery to supply the needed amps. When a battery is under charged (low voltage level) there is insufficient "pressure" to push the required amps through the starter, so heat develops quickly throughout the circuit. Subjecting the starter to a low voltage/high amp draw scenario on a regular basis will lead to cumulative damage to the starter as well as other links in the circuit (key switch, starter solenoid, cables/wires/connectors) Always buy the largest amp capacity battery you can get that will fit in your "whatever" , keep it fully charged,........and you will have a happy life.