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Getting a shockwhen trimming drive down

louc

Regular Contributor
Here's a weird one...I hav

Here's a weird one...I have an 88 4.3 Cobra...and when I trim the drive down with the engine running in the water...I get a shock from the throttle control if I am touching the steering wheel (stainless destroyer style wheel). I didn't think that enough current went throught the trim system even if a wire rubbed through inside the handle that it could give you a shock...maybe because it's a high amp circuit? I also wondered if some of the high voltage from the ignition system could be somehow getting into the trim system and trying to reach ground through the throttle handle..it won't shock me unless I am touching the metal steering wheel at the same time. Any ideas of what to check?
 
The trim circuit in the handle

The trim circuit in the handle is a fairly low current circuit as all it's doing is energizing a relay back at the pump. I assume you've tried it without the engine running? Does it also do it when you trim up?
 
It does not do it with the eng

It does not do it with the engine off and does not do it when trimming up.
 
"Geez...I don't know Lou,

"Geez...I don't know Lou, I guess I would check around the pump maybe for shorted wires in the up circuit, since it's a 50 amp circuit, it would take a good short to blow the fuse."
 
"Bob thanks for trying to figu

"Bob thanks for trying to figure this out, I spoke to my mechanic today, these guys are great, they were trained by OMC back in the old days, and he said it is possible to get a shock if a wire in the control rubs through just enough, but it may not be enough to blow a fuse in the trim circuit. He advised looking at the wiring in the handle and look for bare spots."
 
Well I took a look at the remo

Well I took a look at the remote control and played around with the wires...basically what I found was that the position of the wires was a factor in if you got a shock or not...there is a grommet that is supposed to hold the wired in position as they pass into the control box...this was pulled out of the hole it is supposed to be in and probably is allowing the down wire to chafe against the housing...if I moved the wires a certain way I didn't get the shock...So I'm going to take the handle off and see how far the wires will pull out..and use liquid electrical tape on them and then use trim adhesive to hold the rubber grommet in the hole so it doesn't come out again....
And even though this is a 12V circuit....there are enough amps to give you a good shock..and my control is the standard OMC one so many boats have this control....and can have the same issue...
 
"Good find Lou.....sounds like

"Good find Lou.....sounds like you've almost got it nailed, maybe it would help if you could drag one of your feet in the water while touching the wheel and trimming at the same time
rofl.gif
"
 
I had a similar problem. the i

I had a similar problem. the insulation in the wires inside of the throttle lever wore through. This caused a short and the unit would rise up by iteslf at random and occasionally I would get a shock when touching the throtle. Take the throtle handle apart where the trim wires run down it and look for exposed wires.
 
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