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Infantryhammer
06-04-2011, 06:45 PM
I have a 2003 X7, and I was going along just fine at 2500 rpm or 23 MPH, and all of the sudden, nothing. I am an electrician by trade and a pretty good mechanic. I do all the maintenance on my boat and I am anal about the upkeep of my boat.

So far this is what I have found. I have no power to the fuel pump or the fuel pump relay. The fuel pump fuses are fine. The wires on the kill switch are fine and the switch has been rung out and is fine. I'm starting to think that the ECM is the problem. With the key in the "on" position, the fuel gauge reads the proper fuel level, but when the key is in the "start" position, the fuel gauge reads empty, this has never happened before. The enigine turns over, and will start if I add fuel directly into the throttle body.

Any advice would be very helpful, I need to get this fixed quickly. I was able to get a tow to a private dock and the boat is miles away from my trailer or a launch ramp. So far the dock owner has been very nice and understanding. However, I do not want to push my luck with his empithy.

Thanks in advance,
Adam
Stockton, CA

JimN
06-04-2011, 07:08 PM
I have a 2003 X7, and I was going along just fine at 2500 rpm or 23 MPH, and all of the sudden, nothing. I am an electrician by trade and a pretty good mechanic. I do all the maintenance on my boat and I am anal about the upkeep of my boat.

So far this is what I have found. I have no power to the fuel pump or the fuel pump relay. The fuel pump fuses are fine. The wires on the kill switch are fine and the switch has been rung out and is fine. I'm starting to think that the ECM is the problem. With the key in the "on" position, the fuel gauge reads the proper fuel level, but when the key is in the "start" position, the fuel gauge reads empty, this has never happened before. The engine turns over, and will start if I add fuel directly into the throttle body.

Any advice would be very helpful, I need to get this fixed quickly. I was able to get a tow to a private dock and the boat is miles away from my trailer or a launch ramp. So far the dock owner has been very nice and understanding. However, I do not want to push my luck with his empithy.

Thanks in advance,
Adam
Stockton, CA

Look for the three relays and make sure you have 12VDC on pin 85 or 86 ofr each relay (depending on which has the red B+ lead). The ECM provides a grounding connection, not positive voltage, so I have doubts that the ECM is bad. I think the fuel pump relay will have a green/white trigger wire- you can verify this with a digital multi-meter or LED test light with the clip on a +12VDC source and you should see the LED or meter indicate a ground source for three seconds when the key is turned to ON or continuously while cranking. If you see the grounding signal, use a jumper across pins 85 and 86 for the fuel pump relay- you should be able to hear the pump running but you'll need to make sure the pump is exposed first. If you don't hear it running, verify the connections to the pump (the hot lead is probably pink and the ground should be black). Your fuel pump output is pin 30 and the 12VDC terminal is 87 (the pinout is on the case of the relay).

Infantryhammer
06-04-2011, 09:08 PM
Cool, as soon as it stops raining I will try the jumper.

Thanks for the help,
Adam

Cloaked
06-04-2011, 09:25 PM
Cool, as soon as it stops raining I will try the jumper.

Thanks for the help,
AdamYou can also (try) manually maneuver the safety switch lever to make sure it's in the proper location for the neutal position. Push it fartherst back (away) from the engine. That should be the neutral safety position.

Engine Nut
06-05-2011, 10:18 PM
Look for the three relays and make sure you have 12VDC on pin 85 or 86 ofr each relay (depending on which has the red B+ lead). The ECM provides a grounding connection, not positive voltage, so I have doubts that the ECM is bad. I think the fuel pump relay will have a green/white trigger wire- you can verify this with a digital multi-meter or LED test light with the clip on a +12VDC source and you should see the LED or meter indicate a ground source for three seconds when the key is turned to ON or continuously while cranking. If you see the grounding signal, use a jumper across pins 85 and 86 for the fuel pump relay- you should be able to hear the pump running but you'll need to make sure the pump is exposed first. If you don't hear it running, verify the connections to the pump (the hot lead is probably pink and the ground should be black). Your fuel pump output is pin 30 and the 12VDC terminal is 87 (the pinout is on the case of the relay).


Here is a link to a wiring diagram that a might help you.

ftp://ftp2.indmar.us/Wiring%20Diagrams/MEFI%204%20Series%20Diagrams/MEFI%204%20-%205.7.pdf

JimN
06-05-2011, 10:37 PM
Here is a link to a wiring diagram that a might help you.

ftp://ftp2.indmar.us/Wiring%20Diagrams/MEFI%204%20Series%20Diagrams/MEFI%204%20-%205.7.pdf

This should be added to some kind of sticky or in the technical area- I got my last manuals in Oct of 2000, so they may not have this- they're in my basement because I don't use them as often as the earlier ones.