working on my scag today and trying to get it to run. had ahrd start issue with it when put away for winter, checked for spark its ok , checked fuel lines, ok, replaced fuel filter, ok, turn on key try to sart but no fuel to fuel pump. checked fuse by ignition switch ( 20 amp ) its ok . little black relay above pump clicks when key is on and trying to start. checked all wiring connections for corrosion and all looks ok. where or what do I check now. Oh I put power directly to pump and it runs so its not dead.
need help no power to fuel pump
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davbell22602
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If you have power to pump and its not pumping then fuel pump is bad. Thats if its setup like a automobile fuel pump.
reynoldston
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I really don't know how the fuel system design is on your unit. If it is fuel injected you need high fuel pressure to open the ejectors. If it is carburetor style just a low pressure pump to get fuel to the carburetor. If it is a fuel ejector system you will need to get the right psi number in order for it to run.
Let me clarify something, When trying to start as if nothing is wrong that's when im not getting any power to the pump, if I put power to the pump disconnected from the machine wiring it will run so there has got to be a fuse, circuit breaker , relay or something that isn't sending power to the pump, this is where im looking for guidance to see where to look next. Its a 29 dfi Kawasaki motor
reynoldston
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OK it is fuel injected. With a fuel injected engine fuel pressure is very important. You don't want too much or to little. My very first step would be is see what PSI this unit needs to run and test it for that. Yes you would have a fuse or circuit breaker and a relay. The relay is just a on and off switch and a fuse or circuit breaker is just that. Just guessing at this I would say you need something to regulate the fuel pressure witch in turn would tell the relay to turn on and off. Seeing this is called a Digital fuel injection I would say it would need a circuit board (small computer) plus a fuel pressure regulator. This is hard to give advice from the side line on something like this. You will need positive and negative power to this circuit board.
I think im going to be all set the dealer I bought it from had an open house day today lunch and all and the scag reps were there. Talked to a rep and he told me to check a solenoid and or the wiring at it and that should be the issue hes seen it before. thanks for all that chimed in
wjjones
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A clogged fuel filter could restrict the psi to the pump too. Let us know what you figure out.
Ok machine is all fixed, the issue was the power feed wire from the fuel pump to where it plug into the relay switch that's mounted behind the oil cooler on the motor. In order to get to this you got to undo the two relay switches that's screwed to the block, disconnect all wires to ecm and etc etc etc take wires out from under and around rops cage, re connect then wiggle and check with test light. scag rep said this is common area of issues. also he told me to make sure all contacts on the ecm are ok and not corroded off. when I put the wires back where they belong I will coat with dieelectric grease again.
wjjones
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Good to hear you got it fixed up. I guess the vibration, etc is what caused the loose connection?