Motor Won’t Shut Off…Again

[johnyrude200]

Same motor from my other post…’82 35hp. Already checked the control box that is OK (it is a my test control box same one I use for all motors in teh test tank before boat trials). On the motor side, I ran into one of these same situations a few weeks ago (similar motor…25 thru-hub exhaust model from ’85) where the motor wouldn’t shut off at the key switch. With that motor, it was a faulty trigger under the flywheel.

I’m thinking I have the same issue here because the kill function isn’t very complicated…? I mean, normally the black lead from the power pack would be hooked into a stop button with the other end of the wire grounded to the motor. In the remote control situation the 2nd black lead off the wiring harness that is grounded is just the other end, with the key being the ‘stop’ button when in the off position.

I suppose I could switch power packs first to rule to rule out a bad stop circuit in the power pack too…

Or…bad trigger again?

[dan-in-tn]

Its the black/yellow stripe wire from the pack that is the kill wire. It has to be grounded to stop the engine. Either through the ignition switch or the kill switch. You didn’t mention the black/yellow wire? Broken in the amphenol connector could be your problem?

Dan in TN

[johnyrude200]

Ill do some sherlock holmes work with my continuity meter tomorrow and report back.

The last time I ran into this situation it was a faulty trigger.

Not that tracing this type of basic issue is a big deal but it seems 60% of the time with these motors I rehab (which makes up 90% of my inventory), they are those oddball situations that the marinas or shadetree mechanics gave up on.

[1946zephyr]

A motor that refuses to quit. Thats everones dream…..

[PugetSoundBoater]

quote 1946Zephyr:

A motor that refuses to quit. Thats everones dream…..

X2

"Some people want to know how a watch works, others just want to know what time it is"
Robbie Robertson

[billw]

The big, red, remote control harness plugs are also a problem area for no stop. (and no crank, no choke, etc, depending on which pin in it has failed.) Failures can occur on both the engine and control sides of the connection. Absolutely, ohm out the whole circuit. If it’s testing okay, don’t forget to wiggle and pull at the wiring, as you test.

Long live American manufacturing!

[jerry-ahrens]

A poor connection at the anphenol connector is common. Use a little rubbing alcohol to lubricate the rubber connector before plugging in. With the ignition off, you should have continuity to ground [with Power Pack disconnected] at the black/yellow lead. You may have a faulty stop circuit in the power pack, also a possibility.
After rereading all of this,I see that Dan has already pointed this out. 🙂

[fleetwin]

I really don’t see how a bad trigger/sensor could cause the engine not to shut off, but I know, never say never…
I’m onboard with all the advice concerning the big red plug, and faulty amphenol pins/sockets/connections.
You could simply push the pack stop lead out of the rubber connector, then jump it to ground while running to rule out all of the above. The pack itself is to blame if the engine won’t shut down when the pack stop lead is manually grounded while running.

[johnyrude200]

I don’t claim to have the answer behind that bad trigger, but on the prior motor (not this one), I traced continuity throughout the length of the stop circuit and it tested fine, including swapping powerpacks on that motor. Tracing that black lead under the flywheel to the trigger, that was all that was left in the chain. I opted to swap out the trigger and it fixed the issue.

Didn’t get a chance to look at this 35hp motor yet earlier today but will get back at it tomorrow (Sunday). Great advice on the powerpack test. Always nice to have a simple way to rule something out quickly.

[dan-in-tn]

Sensor/trigger doesn’t have anything to do with the kill circuit of the engine.

Dan in TN

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