Replacing !987 Yamaha Original Tach With Oil,

[Whaler785]

first, Hi the Replacement Tach is Color Coded different than Old Tach and seems to be completely powered differently than new Pro Tachometer Assembly With oil 6Y5-83540-05-00 Yamaha says its the part I need of course no instruction.
If I'm understanding the new one, the 3 warning wires @ lights Black/Orange to all 3 are Ground return for Gages And  Yellow power going into Top with Green Lead & Ground powers the Tach And warning Lights.
Whereas the Old Tachs original 3 wires @ warning lights are Yellow or 12v w ignition on @ and No Yellow 12v going into the top with Green & Ground leads.
Do I need to just reverse all this?

[Capt. Bob]

Yamaha has been through a number of gauge changes over the years. I'm not sure that the model you have will be fully functional on your older motor.

Do you have the gauge # from your old gauge?

[Whaler785]

Yes

[Capt. Bob]

Yes

And????

[Whaler785]

Sorry, still trying to figure this Forum out. and Thank you very much for trying to help me figure this out.
So No #, can't find one anywhere. Even have an original manual that came with it new, nothing.                             Thought U asked if I still had the Old Tach.
Looked many parts places for original Tach and all they say is no longer available.
Thinking of trying 1 other place to check, Boats.net

[Whaler785]

can't find #, When I called Yamaha they told me this was the replacement I needed
all the oil warning leads are the same RYG at all 3 warning light
what's different is how it's powered seems to me and of course the 4 pt. harness plug (old round, new square)
old which has Yellow (12v w/ignition on) at all 3 warning lights
New Has Black with Orange dashes which I believe is Isolated accessory Grounds at all 3 warning lights
New has yellow coming out with BL ground & Green Tach sender
I was thinking i could send power to yellow lead and ground out the 3 BK/OR leads @ bulbs

[Whaler785]

Good morning Capt. Bob Going to do my best to stay on top of the water
posting better pics.
After spending literally Days searching for a replacement, then days trying to find and understand new color codes
and getting this 1 because Yamaha said so $$
So you don't think all the functions will work. At the very least I want the Tachometer to work, the warning lights would b nice. But he Tach tells me most everything Important going on with outboard. Had this for a long time and my ears & nose tell me a lot also.
At this point what I don't Understand is if old Tach only has BK & Gr (Tach Signal), did the power to it come from the Green?
And if so, why does the new 1 have Bk, Gr & Yellow(12v)

[Whaler785]

poop sent the same pic twice, on the west coast, just got moving ;-}

[Whaler785]

Hello Capt. Bob, Took some deep searching and found an adapter harness made just for this Yamaha problem. why Yamaha couldn't tell me about this I'll never know
After they switched the wiring and shape of harness they also made the adapter. 6E5-82541-00 for the warning lights, Then power & wire the Tach. came up with power after ignition doing nothing in the harness. Home free.
Thanks Again for at least looking at it.

[Capt. Bob]

I apologize for the delay. We (Yamaha owners) have had our problems with finding gauges that worked with our older motors. They "upgraded' (or changed to make/save money) through the years and finding NOS gauges was a major search and eBay gamble.

Glad to hear that you can now use a modern gauge on an older motor and that Yamaha makes a cable to allow that. Thanks for the digging. I'll keep that in the back of my mind if/when it comes up again.

Good luck.