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wiring diagram help 1978 Evinrude 25852C 25hp

motiondave

Contributing Member
Hello good people, hopefully someone can point me in the right direction.
I have an [h=1]1978 Evinrude 25852C 25hp[/h]that Im trying to wire up.
I have 5 wires coming out of the loom, but not sure what does what.
They are
Black
Black/yellow trace
red/purple trace
yellow/red trace
purple/white trace.
as well as the usual black and red battery cables

Im unable to find out what does what. Can anyone please advise what each wire does?
Kindest Regards, David Lane.
 
Black/yellow--engine stop (ign off)
Black ground (other side of stop ign off)
Red/purple--12V source from + cable at solenoid
Yellow/red--start
purple white--choke or primer
 
Black/yellow--engine stop (ign off)
Black ground (other side of stop ign off)
Red/purple--12V source from + cable at solenoid
Yellow/red--start
purple white--choke or primer

thanks man,
so is black the general ground?
so, to make ign switch, id use black/yellow and black ground?

start would be black and red/purple wires?


or yellow/red , black.]

and push button momentary black and purple / white for choke?

Pardon me for being stupid.
Regards, David.
 
So what are you trying to do, use push buttons instead of a key switch?

Long story made short:
A switch connects black and black/yellow together to stop the motor
A switch connects red/purple and red/yellow together to make the starter run
A switch connects red/purple and purple/white together together to choke.

Doo not under any circumstances connect 12V to the Black/yellow in any way or fashion, or it will cost ya.
 
I believe you would save $$ by having a shop install the proper key switch.

I asked a few places, they must be really useless around my area, and they asked what each wire does.
most marine shops mechanics charge waaaaay too much for small jobs, and a car auto elect is cheaper but needed help with wiring.
so thanks for the help on wiring diagram layout.
 
12 volts from the battery goes to one terminal on the solenoid.----From that same terminal 12 volts goes to the key switch.-----From the key switch 12 volts is fed to the solenoid ( one small terminal only ) to close the solenoid to crank the engine.-----12 volts is fed to a choke solenoid too.--------The ignition switch opens between the 2 M terminals to run the engine.-----Closes between 2 M terminals to stop the engine.-----12 volts is not used to make spark at the plugs.----The magneto does that.-----If you makes mistakes on simple 12 volt circuits it can cause you a lot of grief !!
 
Surely you must know that it is copyrighted. But one last time, I'm going to try to tell you how it goes.

At key switch:
"Bat" terminal--Red/purple
"Start" terminal--Red/yellow
"Choke" terminal--purple/white
Raised "M" terminal--black/yelllow
Other "M" terminal--black
"A" terminal--purple for tachometer, otherwise not used

At solenoid:
Big post on one side--+Battery cable AND a couple of red wires, one of them going to a fuse, then from fuse to red/purple wire to key switch
Other big post--starter cable
One small post--red/yellow
Other small post--black to neutral start switch. Other side od neutral start switch is grounded. (not to be confused with black from key switch)
Small posts are interchangeable.

Other wires coming from key switch cable:
Purple/white goes to choke or primer
Black/yellow--to a small plug then to power pack
Black is grounded
Grey is for a tachometer if you have one.

If you cannot understand this, then you need a good outboard mechanic
 
ok, ok, take it easy, im only asking for help.
thanks for the wiring labelling.

You could buy a workshop manual

You will find a wiring diagram in the ( Seloc) manual on the Boatinfo website but it is not easy to follow Sorry this forum will not allow me to post a link.
 
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