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Buzzz1000

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I have a 98' yamaha 225 and I have recently had to put quit a lot of money in it to try to get it water ready. Anyways right now I'm stuck . The motor is getting fuel and fire, but not cranking. I took the fuel bar off and faced away from the engine and had someone to turn over the engine, all 6 injectors sprayed fuel. After putting the fuel rail back on I pulled 2 plug wires, one at a time and the plugs were firing. The only thing that I'm not sure of is that I had the wife up front to turn the key on for say 3 sec. and turn it back off, then repeated twice, I then checked the little valve stem by pushing in the little valve and fuel would spray out. But if I wait 10 sec. before pushing in the valve then no fuel would come out ( seems as if it would loose it's prime). Of coarse I really don't know anything about the function of the valve stem set-up but I thought I would mention that cause I'm at the point to where I'm stuck. Oh by the way I can crank the engine by using a spray bottle with mixed gas in it, and it will stay running for as long as its getting gas. Guys Please help me out here, thanks
 
i would do a pressure test to the fuel pump it sound like you are losing pressure in the system somewhere it will tell you what the psi should be in your shop manual and also show you the procedure to do the test
 
You probably have a fuel flow problem that is not delivering enough fuel if you can get it started and keep it running with a spray bottle of gas. I don't know a great deal about Yamaha fuel injected 2 strokes but for many 2 strokes when you are first turning the key to start, when it hits the "ON" position the fuel injection pump is engaged to build pressure just before you reach the start position that engages the starter. Seems to me if you just clicked to ON or all the way to START briefly it would build pressure but when you went back to the OFF position the pressure would quickly bleed off as the pump turned off and fuel flowed back through the system. That would explain why after 10 secs, no more spray from that little valve. (that little valve that looks like a tire inflation valve is where you hook up a fuel pressure gage). I'd confirm spark in each and every plug. Pull a plug put the plug wire on hold it with a rag and and touch the base of the plug to the block... Have wife crank engine and look for spark. Repeat with each plug.

If you have spark to all plugs, I agree with John... If you can hook up a fuel pressure gage to that valve and see if it quickly "snaps up" to proper fuel pressure at starting for the engine and holds it with the key left in the ON position seems to me the high pressure fuel pump is OK. IF it takes a while to reach spec starting pressure it could be the fuel injection pump needs replaced. If lucky, it may just be the the internal filter (you can't see it) at the base of the fuel injection pump is clogged. IF you take the fuel line off of the inlet to the fuel injection pump and squeeze your fuel bulb coming right from the gas tank (before any inline Racor filter or under cowling secondary filter) do you get a good flow with minimal resistance at the fuel line feeding the injection pump with each squeeze? IF not, maybe a racor is clogged or an under cowling pre-filter prior to the fuel injection pump is clogged? If you get good flow I'd look to that internal filter at the base of your fuel injection pump that will take some wrenching to get to. Go to SIM yamaha on line and look at the diagams for your engine. You'll see the hidden filter I am talking about.
 
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