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Merc 240 EFI won't start - no spark at the plugs

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2004utopia

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I have a 2004 Utopia 185 with the Mercury 240 hp EFI engine. I tried to start it today for the first time this year and it wouldn't start. The engine turns over but it wouldn't fire so I pulled all of the plugs thinking they may be fouled , which they weren't. I grounded three of the plugs on the motor and cranked the engine and I found that there was no spark at any of the plugs. Any suggestions on how to fix this would be appreciated. Thanks in advance!
 
1. Engine cranks but won’t start

1.0 Lanyard stop switch in wrong position.

Reset lanyard stop switch.

1.1 Weak battery or bad starter motor, battery voltage drops below 8 volts while cranking
(ECM cuts out below 8volts) (Fuel pump requires 9volts)

Replace/charge battery.
Inspect condition of starter motor. Check condition of battery terminals and cables.

1.4 Blown fuse

Replace fuse. Inspect engine harness and electrical components.

1.5 Main Power Relay not functioning

Listen for relay to “click” when the key switch is turned on.
 
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Other then pulling the lanyard off and replacing is there something elce to do to reset the lanyard stop swithc? What fuse are you talking about? Where is it located?

Thanks I will check this out and see what happens.
 
If you're getting no spark on ANY plugs, you may have a problem with the CDI disable circuit. This is a black-with-yellow wire that runs all over the boat. Anything grounding that wire disables all six CDI's and prevents sparking. Things that are connected to that wire include:

1) Keyswitch
2) Killswitch
3) RPM limiter (on engine)
4) "Throttle Guardian" (black box behind steering column)

If you're staring down at the top of the engine, there is a wiring harness coming up from the right (in this case, port) rear from the CDI's on that side. There will be a black-with-yellow wire. It will connect to one of the two black boxes sitting on top of the engine there, and a black-with-yellow will continue on and eventually run up toward the console. You can disconnect that wire at the top of the CDI column, next to the on-engine rev limiter, via its bullet connectors. Do that and see if you get spark. If so, check the four components listed above - pretty likely you'll find one of them is holding that wire grounded.

Report back!
 
I pulled the fuses and they are all intact. I also fully charged the battery, pulled the kill switch lanyard and replaced it. I then tried to start the motor I hear the fuel pump "clicking" but still nothing. Any other ideas?
 
Is the black with yellow wire running at the back of the engine where the plugs are? I had a pretty good lokk and can't seem to find this wire. You wouldn't have a picture that shows what i'd be looking for?? What are the CDI's? I'm probably not not looking at the right items on the engine. Tomorrow I'll pull the Keyswitch/killswitch and see if I can find the wire there.
 
Is the black with yellow wire running at the back of the engine where the plugs are? I had a pretty good lokk and can't seem to find this wire. You wouldn't have a picture that shows what i'd be looking for?? What are the CDI's?

CDI's are the black boxes that connect to the spark plugs. There are six of them, one near each plug on the "rear" of the engine. They have a four pin connector that ties into a harness that runs to each CDI. Follow that up toward the top of the engine and you'll find a black with yellow wire. Follow that along and you'll find it connects to one of the two slab-like black boxes mounted on the top of the engine (that's the rev limiter).
 
I pulled the engine cover and still couldn't find the black with yellow wire. I then pulled the pad in front of the steering wheel and looked at the wire going to the kill switch and that looks like it is black with yellow. So I went back to the spark plugs and the CDI's and I still can't find a black with yellow wire. The closet one I could find is purple with yellow. I'm thinking I might be forced to have a mechanic have a look at ti and see what they can do. Thanks for the directions/suggestions and if you have anything else that you think I could do please let me know.
 
I pulled the engine cover and still couldn't find the black with yellow wire. I then pulled the pad in front of the steering wheel and looked at the wire going to the kill switch and that looks like it is black with yellow. So I went back to the spark plugs and the CDI's and I still can't find a black with yellow wire.

I didn't realize you have a 2002+ version of the 240EFI. It has a different ECU and the grounding signal goes to the ECU, not directly to the CDI modules.

The black-with-yellow is indeed the wire you're looking for, coming back from the driver's console. It runs to the ECU on the engine. Then a separate wire, black-with-GREEN, comes back out of the ECU and runs to the CDI's. It connects to pin B of each CDI in parallel.

If you can disconnect that common black-with-green wire coming from the ECU to the CDI's you can run the test. Alternatively, if you can disconnect that black-with-yellow wire coming from the driver's console you should get the same effect.
 
Well I couldn't find the wires so I broke down and took it to a local boat mechanic and after looking at it and serveral hundred dollars later they told me it was a faulty crank position sensor. At least the boat is running even thought I think I was over charged on the labour! Anyways Thanks for all the help it is appreciated.
 
Well I couldn't find the wires so I broke down and took it to a local boat mechanic and after looking at it and serveral hundred dollars later they told me it was a faulty crank position sensor. At least the boat is running even thought I think I was over charged on the labour! Anyways Thanks for all the help it is appreciated.

I bet we would have gotten there eventually, but hey - it's fixed and you're on the water. Congrats and have fun!
 
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