Wiring tach from Johnson controls.

bonz_d

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The plug on the bottom of the control has just one gray wire coming from it going to a trim gage. Is there a way to wire the tach from that wire or from the trim gage terminal with that wire?
 
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Re: Wiring tach from Johnson controls.

What engine?

What you're describing doesn't add up, unless someone has done some redneck engineering somewhere along the way. The tach signal should be on a grey wire that originates at the rectifier or a terminal block the rectifier is connected to, goes to the remote control, and from there through that 3 pin plug to the tach. The trim signal originates at the trim sending unit and goes up to the trim gauge "S" terminal and it's a white/brown wire. All of this is somewhat generic, but it's similar for all 3 engines that I have manuals for.
 

bonz_d

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Re: Wiring tach from Johnson controls.

Sorry, just to clearify. Right now there is no tach. I want to add one.

Original engine was a 1988 Evinrude 70hp, replaced by a 1983 60hp, The 3 pin plug has just one wire which is going to a trim position gage. Does this help? Is there a different 3 pin wire I should have? Can I connect both a tach and trim gage through the control?
 

Joe Reeves

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Re: Wiring tach from Johnson controls.

The rubber plug you describe is there for the plug in type tachometer... it simply plugs in and the tachometer works. On the other side of that plug is a:

Purple Wire: 12v supply for the tachometer.
Gray Wire: Sensor lead for the tachometer.
Black Wire: Ground lead for the tachometer.

I suspect that someone has used one of those connections to either power or ground the tilt gauge. Look on the back of the tilt gauge and let us know what lettered terminal it is connected to.
 
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Re: Wiring tach from Johnson controls.

Here's a wiring diagram which should apply to your engine, it was in a link in the top secret files at the top of this forum.

http://maxrules.com/graphics/omc/wiring/78-84_3-CYL_EL.jpg


Here's a diagram that shows a typical tilt/trim system

http://maxrules.com/graphics/omc/wiring/TnTwiring.gif


And here's one that shows typical wiring for the remote control box

http://maxrules.com/graphics/omc/wiring/REMCONTBOX.jpg




You're probably going to have to use these as a guide and do a little detective work. The grey wire that comes from the terminal block near the rectifier and goes to the big red plug is the tach signal. It should continue forward to your remote control box and be accessible on the 3 pin plug which is on the remote control. The purple is +12 V, and black is negative/ground.

On the tilt/trim diagram there's a brown/white wire coming forward through a 5 pin connector, and ending up on the "S" terminal of the trim gauge, that's the trim signal from the sender. The brown/black wire shown going to the trim gauge "G" terminal is ground.

I'm afraid I won't be able to offer much more help than that without having access to your boat (especially since it sounds like there's some non-standard wiring in your boat).
 

bonz_d

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Re: Wiring tach from Johnson controls.

When looking at the tilt trim diagram if you look next to the shift/throttle lever it shows the key and warning horn then the 3 pin plug. There it shows one wire exiting the plug to the I terminal on the gage. Which is also the pin that looks to be suppling power in the diagram. This is exactly how this is wired in the boat.

A tach should have 3 wires coming from that 3 pin plug right? So if I change to a 3 wire plug at the control for the tach I am assuming I could then go from the purple wire on the tach to this I terminal on the gage and everything should work? Does this sound right?
 
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Re: Wiring tach from Johnson controls.

When looking at the tilt trim diagram if you look next to the shift/throttle lever it shows the key and warning horn then the 3 pin plug. There it shows one wire exiting the plug to the I terminal on the gage. Which is also the pin that looks to be suppling power in the diagram. This is exactly how this is wired in the boat.

A tach should have 3 wires coming from that 3 pin plug right? So if I change to a 3 wire plug at the control for the tach I am assuming I could then go from the purple wire on the tach to this I terminal on the gage and everything should work? Does this sound right?


Yes.
 

bonz_d

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Re: Wiring tach from Johnson controls.

Great! And thanks guys. One more issue to cross off the list.
Now it's off to bed so I can work all night. 3rd shift bites.
 
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