Help, Motor won't start. Merc 454 Mag EFI
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Help, Motor won't start. Merc 454 Mag EFI
So I have twins and this is what I've tried and narrowed down thus far.
Port Motor cranks, has spark, is pumping fuel to rail, no blown fuses found.
Turn the key on but do not get the warning sound, when I turn key it ticks like batt is dead but they're not. Changed safety switches from starboard side and same results. Port side sounds and fires right up. Both motors were running fine 3 weeks ago and have not used boat since.
I feel like some safety switch or something is keeping fuel from pulsing through injectors. Pulled one plug after cranking and was completely dry and no smell of fuel. Tried what seems like everything for 6 hrs on launch ramp and luck. Ruined a good day of boating. Need fixed if you have any advice, id appreciate it. Thanks guys
Port Motor cranks, has spark, is pumping fuel to rail, no blown fuses found.
Turn the key on but do not get the warning sound, when I turn key it ticks like batt is dead but they're not. Changed safety switches from starboard side and same results. Port side sounds and fires right up. Both motors were running fine 3 weeks ago and have not used boat since.
I feel like some safety switch or something is keeping fuel from pulsing through injectors. Pulled one plug after cranking and was completely dry and no smell of fuel. Tried what seems like everything for 6 hrs on launch ramp and luck. Ruined a good day of boating. Need fixed if you have any advice, id appreciate it. Thanks guys
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Join Date: Apr 2007
Location: Northern, KY (Cincinnati) Lake St Clair, MI Norris Lake, TN
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If it's the starter slave I believe you would get one single click. If the motor is turning over it's not the starter. When you turn the key to the ON position do you hear the fuel pump kick in?
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The fuel pump is manual and the reservoir on top of motor is pressurizing. When I turn key I don't get the warning sound like I should. I turn the key to the run position and it makes a clicking sound at dash instead. The fuel rail has fuel, it's getting plenty of spark at plugs cause got shocked testing fire, but pulled a plug and was completely dry and no smell of fuel on it which lead me to believe no fuel is getting into cylinders. Not neutral safety cause motor cranks. Switched safety switches at dash and makes same noise. No warning beep.
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I would check the grounds at the engine block from the negative battery, and the ground stud where engine harness grounds get grounded to. The alarm system gets grounded thru the engine. The alarm gets + power anytime the key is on. It goes off, when any of the circuit switches close, whether it be coolant temp, low oil pressure, fuel pressure, etc.
Chances are your alarm not working, has something to do with the engine not starting. The engine has a mechanical pump, but also has an electric pump. There is both a fuse and a relay for the electric pump. Again, this electric pump will not work if there is a bad ground. After winter time storage, is normally when these ground issues come up.
A test light, and wiring schematic will go a long way here. But I'd start with checking for clean ground connections. I believe the buzzer will have the purple wire going to one side, and tan/blue to the other. Tan/blue is the ground side. Before anything you can test for power with a test light at the purple wire on the buzzer with the key on. If you have power there, Leave the key "on", and play with those grounds back at the engine, listening for the buzzer to sound.
Chances are your alarm not working, has something to do with the engine not starting. The engine has a mechanical pump, but also has an electric pump. There is both a fuse and a relay for the electric pump. Again, this electric pump will not work if there is a bad ground. After winter time storage, is normally when these ground issues come up.
A test light, and wiring schematic will go a long way here. But I'd start with checking for clean ground connections. I believe the buzzer will have the purple wire going to one side, and tan/blue to the other. Tan/blue is the ground side. Before anything you can test for power with a test light at the purple wire on the buzzer with the key on. If you have power there, Leave the key "on", and play with those grounds back at the engine, listening for the buzzer to sound.
#10
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I would check the grounds at the engine block from the negative battery, and the ground stud where engine harness grounds get grounded to. The alarm system gets grounded thru the engine. The alarm gets + power anytime the key is on. It goes off, when any of the circuit switches close, whether it be coolant temp, low oil pressure, fuel pressure, etc.
Chances are your alarm not working, has something to do with the engine not starting. The engine has a mechanical pump, but also has an electric pump. There is both a fuse and a relay for the electric pump. Again, this electric pump will not work if there is a bad ground. After winter time storage, is normally when these ground issues come up.
A test light, and wiring schematic will go a long way here. But I'd start with checking for clean ground connections. I believe the buzzer will have the purple wire going to one side, and tan/blue to the other. Tan/blue is the ground side. Before anything you can test for power with a test light at the purple wire on the buzzer with the key on. If you have power there, Leave the key "on", and play with those grounds back at the engine, listening for the buzzer to sound.
Chances are your alarm not working, has something to do with the engine not starting. The engine has a mechanical pump, but also has an electric pump. There is both a fuse and a relay for the electric pump. Again, this electric pump will not work if there is a bad ground. After winter time storage, is normally when these ground issues come up.
A test light, and wiring schematic will go a long way here. But I'd start with checking for clean ground connections. I believe the buzzer will have the purple wire going to one side, and tan/blue to the other. Tan/blue is the ground side. Before anything you can test for power with a test light at the purple wire on the buzzer with the key on. If you have power there, Leave the key "on", and play with those grounds back at the engine, listening for the buzzer to sound.