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1974 Mercury 500 50 hp wiring

D

DeweyDeb

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rewired my outboard because all the wires were corroded, now when I turn the key it does nothing? Can anyone tell me where does the control box get power from? is it the Solenoid?
 
Thank you, Yes that is what I went off of. but it seems like I am not getting power to the Control Box, or the Switch Box? be cause I can take a wire straight from Battery to the red wire that goes to control box and Rectifier, and it will crank over? any ideas? does the Control Box get power from the Solenoid?
 
Yes I have it wired exactly like that and when I turn key it will not crank? but if you look at that diagram and what I did is take power straight from battery and hooked it up to the red wire that comes from Control Box, and hooks to Rectifier, and it will crank?
 
Yes what I did is cut the harness and pulled enough to rewire, but it seems like I am not getting power to the ignition switch so what color wire would have the 12 volt power if I open the control bot and check? Thanks
 
the yellow goes through the neutral switch and then goes to pick the solenoid when the key is in start position...this is a safety feature to keep the engine from starting in gear..you are not going to fix this problem by jumpering this or that and see what happens...troubleshooting is the way to go before you burn up something...
what wiring did you replace?is this motor new to you?
 
Hey Papyson, This is new to me, but I am very good with doing things on my own... and what I am thinking is that I am not getting power to the Control Box? and was wanting to know how to find that out? what color wire would be feeding power to it? and then I could take a meter and work my way back.. Does that sound like what you would do? Thanks,
 
Why I am confused Kimcrwbr, is if you look at diagram the red wire goes from the Rectifier to the ignition switch so how does the rectifier feed power to it? the is 2 other yellow wires off of it going to top of motor?
 
I have it down at camp so I will check things this weekend and I want to thank you guys for all your help and will know more after I get back.. Thank you very much
 
i apologize if i sounded abrupt in prior entry...in another entry on this problem you state that you have a multi meter and know how to us it....so lets try this approach..(red feeds 12,7v to power box btw)....before you disconnect the battery verify that you have have voltage at the starter...then disconnect the battery..place the shift arm in neutral...disconnect the pick wire to the starter solenoid...with the shift arm in neutral and the key in the start position you should have continuity between the positive(disconnected) wire coming from the battery and the wire that you disconnected from the starter solenoid pick wire that you disconnected...you now have only a few things in the circuit ...the neutral switch and the start position on the key switch and a plug or two..plus your wiring of course...this is a safe approach and will not damage anything...i got to cut some grass if i am going to camp tomorrow so i wont be looking at this til late today.....
if you replaced the harness i think you did then a mistake is easy to make because you are operating behind that front cover with components on it as i remember..its just been a lot of years since i done it...
Kimdrwbr1 please jump in and double check me...my wife has been in here yakking 19 times while i was looking at this...
 
i should have said red feeds power to the controls...thanks for jumping back in...it has been a long time since i worked on an old 50 but he may have a red wire in the battery compartment just laying there disconnected...seems i remember two wires on the positive post..he never said if he had just got the motor or was familiar with it..an open or short in a motor that's wired correctly is simple to find..a human mistake in wiring can be a little tricky..and could result in component damage in the area he rewired..
 
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