OMC 7.4GL 454 intermittent start w/o key in ignition

Picknasty

Cadet
Joined
Apr 18, 2016
Messages
12
So I had a weird thing happen tonight, I just recently replaced my failing slave solenoid on my 1996 OMC 7.4GL inboard with an Arco SW774. I put in two new 27 group batteries and also replaced a failing ignition key switch. After running the boat in the yard for a 10 minutes and then a few times more of the same thing, I spent another hour and a half or so washing the boat and cleaning up. Here is where it gets weird. I pulled the keys out of the ignition switch and turn all my electronics off but left my battery selector switch on battery 1. I came back out a little later and all of a sudden my starter was engaging the flywheel without the key in the ignition switch! SO I cut the battery selector switch off and it stopped immediately. Any thoughts of where the short may be or maybe I hooked something up incorrectly?

As always, I appreciate the advice and experience of those on this forum.

UPDATE: I've been reading the forums and it seems that others with a problem somewhat similar to this had a the relay/solenoid weld in the closed position allowing power to flow to the starter w/o the ignition switch engaged. BUT if this seems to be an intermittent problem that arose after a hour or so of down time would that point to something else?
 
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HT32BSX115

Supreme Mariner
Joined
Dec 8, 2005
Messages
10,083
I came back out a little later and all of a sudden my starter was engaging the flywheel without the key in the ignition switch! SO I cut the battery selector switch off and it stopped immediately. Any thoughts of where the short may be or maybe I hooked something up incorrectly?

As always, I appreciate the advice and experience of those on this forum.

UPDATE: I've been reading the forums and it seems that others with a problem somewhat similar to this had a the relay/solenoid weld in the closed position allowing power to flow to the starter w/o the ignition switch engaged. BUT if this seems to be an intermittent problem that arose after a hour or so of down time would that point to something else?

Howdy,

It is possible for a solenoid to weld itself closed but it would generally stay closed. not just randomly connect by itself.

I would suggest you get yourself an OEM service manual so you can refer to the wiring diagram. Work backwards from the starter and see why the starter has power, the solenoid has power (if it does) and where that power is coming from.

It sounds like a (simple) trace on the wiring will reveal where the solenoid is getting actuation power from.

Regards,

Rick
 
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