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No spark from ignition, but sparks when bypassed

J

Jwall69

New member
Good morning All
I have a problem with my 60HP 3 Cyl outboard. The boat ran amazing one day, the next day it wont start. It has no spark, but turns over like crazy, and the battery is brand new. I took it to a dealer and he used a bypass cable to connect straight to the motor, and voila, it fired right up and ran like brand new. He told me the problem is between the ignition switch and the plug connection at the motor. He said, if you want to check it out yourself, I wont even charge you for my time, so i took it home. I plan on trying to find the issue myself first. Any suggestions of where to look first, note: it does not have a kills switch, so i cant start there.
 
I'm not a professional mechanic. I do maintain my boats, cars, trucks, and farm tractors however and have for half a century.
My outboard engines are mid sized and are controlled by the remote control box. The box gets 12v power and ground from the engine via the electrical interconnect cable.

The ignition switch supplies 12v power back to the electronics in the engine in the On position and that plus 12v to the starting solenoid in the engine for starting with the key in the Start position. When the key is released after the engine starts, the key switch removes 12v from the starting solenoid but retains 12v power to the rest of the engine as before.
Also in the control switch is a grounding wire that grounds out the ignition system when the key is moved to the Off position and shuts the engine down.

I'd start by suspecting the switch due to wear and contamination, unless you have chafing of the electrical cable (harness) between the engine and control box that may have rubbed the insulation off wires causing problems.

One thing that most boats have now-a-days, is a safety switch controlled by a lanyard that the operator attaches to their person when operating the boat.....now a requirement in Texas. Purpose of this lanyard and associated "kill" switch is to stop the boat if the operator is no longer at or able to control the boat from the driving position. This safety switch is easily forgotten and may malfunction, or the lanyard accidentally pulled out, cutting power off.

A service manual for your engine will furnish you with wiring diagrams where by you can trace out your wiring and locate the malfunctioning object. I buy mine off ebay.
 
Thank you for the reply. I can not see a visual kill switch, there isn't one on the control box, or on the dash. Most sites i have visited also point to a grounding of the kill switch wiring. I will look at those to see if i can find anything strange. It was running like a new motor, then, the next morning , no start. It has fuel, and lots of cranking, but no spark. The mechanic said, its definitely a wiring issue on the boat, or between the 6 pin pug at the motor and the ignition switch. Time to start poking around
 
Water in the keyswitch will do that. Quick way to tell if the keyswitch is bad. Turn the keyswitch to "on" position. Unplug the the engine harness at the motor end. Jump the starter with jumper cables and start the engine. While it is running, plug the harness back together. If the engine shuts off the keyswitch is bad...
 
fitz73222 said:
Water in the keyswitch will do that. Quick way to tell if the keyswitch is bad. Turn the keyswitch to "on" position. Unplug the the engine harness at the motor end. Jump the starter with jumper cables and start the engine. While it is running, plug the harness back together. If the engine shuts off the keyswitch is bad...
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Thanks for that. I will add that to the list of things to try/check
 
That model uses capacitor discharge ignition. Does not need a battery to run. It creates its own electricity.
 
SO, I replaced the ignition switch with a brand new one, still wont spark, But it cranks like hell. Battery is full and holding 13.8V. The mechanic bypassed the boats wiring and connected his lead right to the engines wiring harness and it fires right up. I also disconnected the kill switch wire at the ignition switch and still nothing. Is it worth trying to disconnect the kill switch wire at the engine? there is no ground short in the KS wiring anywhere. There is no kill switch on the boat or motor. So, what else could this be?
 
Jwall69 said:
SO, I replaced the ignition switch with a brand new one, still wont spark, But it cranks like hell. Battery is full and holding 13.8V. The mechanic bypassed the boats wiring and connected his lead right to the engines wiring harness and it fires right up. I also disconnected the kill switch wire at the ignition switch and still nothing. Is it worth trying to disconnect the kill switch wire at the engine? there is no ground short in the KS wiring anywhere. There is no kill switch on the boat or motor. So, what else could this be?
Click to expand...
Now that you have eliminated the switch, have you gone through the remote wiring harness testing like I mentioned earlier? "Stuff" doesn't just happen, its caused!
 
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