Whaler Central - Boston Whaler Boat Information and Photos

Posted by zappaddles on 11/02/10 - 3:34 PM

Just fired off the 2002 70 HP TLRB Yamaha for the first time (on my boat). Started just fine. However, the following happens:

1)The engine won't stop unless the kill switch is activated.

2)The warning horn stays on.

To verify that I'm not back-feeding the ignition switch, once the engine is started, I disconnected all hot leads from the battery and all wires from the ignition switch. It still runs.

Is there something on the engine that might cause this? The only wireing I've touched on the engine is to replace the battery cables and wireing harness due to having moved the batterie forward and not having been supplied an engine harness at time of purchase.

Information is greatly appreciated.

Vince Zappia

Posted by Derwd24 on 11/02/10 - 5:47 PM

I can't speak for Yahama specifically, but I have seen this exact thing happen on OMC (Johnson and Evinrude) engines.

There's a black/yellow wire that comes from each power pack and runs up to the key switch. When the switch is turned to the off position, these wires are connected to ground. If there's no ground present or a bad switch connection, it will prevent the engine from turning off and produce exactly what you are experiencing.

Logic would suggest to look for a hot wire as the problem, as you have, but in this case, ground is what to focus on if Yamaha is similar to J/E.

Edited by Derwd24 on 11/02/10 - 5:51 PM

Posted by zappaddles on 11/03/10 - 4:58 AM

Thanks for the response. Turns out I have the kill switch wires and the white engine stop wire from the engine harness wired incorrectly. You were on-target with your estimation of the problem.

Vince

Posted by tothemax on 09/06/20 - 1:28 PM

I'm having a similar issue with a 1987 Evinrude 150 TX and it only seems to happen when the motor is hot. If I let it cool down the key switch seems to work fine. My project for tomorrow is to clean and check all the wiring and electrical connections verifying the grounds are good and retest. This just started last week. It seems like 3 of cylinders keep running with the key off when it's hot. When it does this I can kill the engine by shifting into gear. Doesn't give me a warm feeling.

One other thing that started about the same time is that under power the motor seems to pulse, like the carbs are starving for fuel. Doesn't seem to run lean just pulses, even on a plane. I'm going to change out the fuel filter tomorrow as well to eliminate any fuel delivery concerns. I have a glass inline filter I'm going to which will let me see if fuel may be an issue. Not sure if this could be related to a power pack issue.

Open to any other suggestions...

Edited by tothemax on 09/06/20 - 5:36 PM

Posted by tothemax on 09/07/20 - 3:04 PM

Will do, thanks

I changed out the fuel filter (Racor filter/water separator) today, added the glass inline filter after the squeeze bulb, and cleaned up the port power pack connections making sure everything was well connected and ground points were clean. This power pack looks relatively new (blue with orange wires going to the coils). The right side looks much older, possibly original. I'll tackle that in the morning and test it. I did fire it up today after I was done and this time it stayed running even while cold. Crazy thing is that the motor starts right up and idles well. The fuel in the filter was clean, no water.

Edited by tothemax on 09/07/20 - 3:08 PM

Posted by tothemax on 09/09/20 - 4:31 AM

I went through the ignition wiring yesterday and spoke with one of the marine mechanics at my local marina. He had a spare switch left over from a job which he gave me. Since I was going through the wiring it was just as easy to replace the switch out. No difference, wiring is correct. When I turn the key off it still seems that a few cylinders keep running. I've ordered a power pack so I can check if that is the issue.

When I was talking with the mechanic he thought that the surging was unrelated, most likely the check valve in the fuel pickup line or possibly a clogged tank vent.