OMC Tach with a 76 Johnson

ddrieck

ddrieck

Senior Chief Petty Officer
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Jul 12, 2007
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This is a mixed one and not sure which area to put this question but here goes.

I'm installing a 1976 Johnson 85hp V4 on my Starcraft this weekend and was wondering if I can still use the original OMC tach that was connected to the old Merc I removed? If so, does anyone have a wiring diagram to do this?

The OMC tach has several pulse settings.

Thanks,
Darren
 
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ezeke

Supreme Mariner
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Sep 19, 2003
Messages
12,532
Re: OMC Tach with a 76 Johnson

What kind of control do you have? If it is a OMC J/E side mount, the wiring for the tach will be inside the control housing with a gray wire taped off.

If the Control is a newer side-mount, the tach wiring is in a three wire plug located on the control below the ignition switch.

The setting will need to be "6p".
 
ddrieck

ddrieck

Senior Chief Petty Officer
Joined
Jul 12, 2007
Messages
673
Re: OMC Tach with a 76 Johnson

The controls are the old Johnson Command Center.
 
E

ezeke

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Re: OMC Tach with a 76 Johnson

OK, you need a positive (purple) feed off the ignition switch "A".

You need a negative (black small "M") off the ignition switch.

Untape and connect the grey wire, which is the sender.

If you want lighting, run a blue wire from one of the other gauges.

Click the thumbnail, please.
 

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ddrieck

ddrieck

Senior Chief Petty Officer
Joined
Jul 12, 2007
Messages
673
Re: OMC Tach with a 76 Johnson

Thank You so much for the help!! This should work out great.....as long as it doesn't snow again. I've been trying to get this old Johnson hung for 4 weeks. Every time I think there is a break in the weather, wammo, mother nature throws a curve ball.

Thank Again,
Darren
 
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