Author Topic: Dash Wiring Schematic? (Read 12452 times)

dorelse · « **on:** December 08, 2012, 11:59:44 PM »

I don't have the schematic in my Clymers book...does anyone have the wiring harness schematic for the 8-pin rectangular connector? Specifically, there's a lt. purple & tan w/white stripe wire that I were tapped into the key switch (along with 6 other power wires) that I don't know what they're for...

Trying to clean up the rats nest:

Hyperacme · « **Reply #1 on:** December 09, 2012, 05:44:52 AM »

Theres one in the "70 Stern drive & Jet" manual ...
http://forum.cgoamn.com/index.php?topic=2919.0

dorelse · « **Reply #2 on:** December 09, 2012, 04:17:18 PM »

I dunno Gregg - that's not looking right either.

I labeled everything before I unhooked everything...and I have the 8-Way rectangular plug from the engine to the dash.

It's possible I have a mashup of different wiring, as my 10/12 Gauge Orange wire off the round plug, turns into White along the way, Red stays Red.

Blue is the Oil Pressure (starts as Orange to the engine plug)
Tan is Temp (starts as Green to the engine plug)
Gray is Tach (starts as white to the engine plug)

Then I have a Purple and a Pink w/Wht Stripe wire that were connected to Battery power at the key switch, but I really can't find any schematic that shows a pink/wht stripe wire.

So I'm trying to figure out what/why they're connected to battery power so I can route them correctly to the new fuse block.

Rich_V174SS · « **Reply #3 on:** December 09, 2012, 04:52:17 PM »

When I upgraded the engine in my boat I had one of those rectangular plugs on my donated replacement harness too but to prevent bad connections in the aging pins I removed it entirely and just used new ring terminals crimped onto the loose wires. I traced each wire back to its respective connection on the engine and made the appropriate connection on the gauge or key switch, didn't care what color the wire was.

Glastronjohn18 · « **Reply #4 on:** December 09, 2012, 05:15:52 PM »

Going by ABYC color standards Pink would come from the fuel sender to the fuel gauge,so pink w/ white could go from the key switch to the fuel gauge.
Purple is usually ignition and could be used as a power source for the instruments.

dorelse · « **Reply #5 on:** December 09, 2012, 07:18:55 PM »

Quote from: Glastronjohn18 on December 09, 2012, 05:15:52 PM

Going by ABYC color standards Pink would come from the fuel sender to the fuel gauge,so pink w/ white could go from the key switch to the fuel gauge.
Purple is usually ignition and could be used as a power source for the instruments.

Hmm...ok. I guess the coding doesn't have to match the function? My fuel sender comes up under the floor is located in the walkthrough to the bow and uses Red/Black wires.

I'll check for power once I get everything wired up and installed.

wexrocks · « **Reply #6 on:** December 09, 2012, 08:12:50 PM »

Those colors sound familiar to me for Merc wiring from late 70's/early 80's... I can check my books tomorrow to find out what it originally was if you like...

dorelse · « **Reply #7 on:** December 09, 2012, 09:01:19 PM »

Quote from: wexrocks on December 09, 2012, 08:12:50 PM

Those colors sound familiar to me for Merc wiring from late 70's/early 80's... I can check my books tomorrow to find out what it originally was if you like...

If you can that'd be great. I'd like the wiring to actually be correct!

Jason · « **Reply #8 on:** December 09, 2012, 10:34:05 PM »

If it were my boat I would do like Rich did and go through it wire by wire and figure it out! Looks like you might want to get rid of your square connection block too. Or at least try and clean it up.

dorelse · « **Reply #9 on:** December 09, 2012, 11:12:12 PM »

I'd like to keep the plug. I know it works and I can unplug the entire dash/gauge at 1 point. Plus, the round pin engine harness, turns into the plug and connects run up to the dash. Its all nicely put together and it'd be nice to keep it that way.

The thing that's bugging me is that this is all Mercruiser wiring...so I shouldn't have to trace each and every wire..they're standardized connection points.

I should be able to look at 2 schematics...the engine harness one, and the missing 8 pin rectangular plug schematic and know what each is for. I just don't have a schematic for the 8 pin plug that runs from the engine bay to the dash.

I know everything but the Purple & Pink/Wht...

And the plug cleans up pretty well when you remove the 8 extra wires that were all tapped and double wired at the keyswitch:

75starflight · « **Reply #10 on:** December 10, 2012, 08:11:36 AM »

I have the same pink and white wire under the dash of Phoenix Rising but it has never been connected to anything. I think it would be used for the volvo engine application. but that is just a guess.

kert0307 · « **Reply #11 on:** December 10, 2012, 01:29:14 PM »

I have the dash wiring diagrams in my book. Fyi, merc used different setups on those plugs for each different motor setup... made it interesting when I used the 140 harness and my 188 motor. I'll get it out and look for you after work today.

wexrocks · « **Reply #12 on:** December 10, 2012, 06:28:28 PM »

Can't seem to find the right info...

where they were connected to the key switch... is that a hot? hot when the key is on? off? both? my question is, could the wires you are trying to find the purpose for be hot leads to things like trim or trailer switch(es), lights, gauge lights, volt meter, or any kind of factory "accessory". if you can't trace it back, maybe just hook it up temporary without those connected and try everything elctrically powered to see what doesn't work.

dorelse · « **Reply #13 on:** December 10, 2012, 06:58:27 PM »

Yep, that's likely what I'll have to do. I honestly don't think they did anything, but yes, they were 'hot' pulling off the key switch along with 4 other wires all tapped off the key switch.

Jason · « **Reply #14 on:** December 10, 2012, 10:03:01 PM »

I looked at the 140 wiring. It has the rectangle connector too. No Pink/White wire but the purple runs from the Key ON terminal to the connector where another purple write runs from there to all the gauges. It appears to apply the power to all the gauges when the key is on. I bet it also apply's power to the coil in the RUN position.

Glastronjohn18 · « **Reply #15 on:** December 10, 2012, 10:13:42 PM »

Just to throw this out there, here is a wire diagram from my '64 -'91 merc shop manual.
It shows a 10 pin round plug but it might give you an idea how the gauges are hooked up.

I see you posted as I'm typing. You should be able to use the 140 as a guide.

dorelse · « **Reply #16 on:** December 10, 2012, 11:24:57 PM »

Sounds like purple is worked out. Here's what I'm trying to 'undo'...there were 5 wires all running off the Key On terminal using this little add on attachment terminal things. (Slide in 1 female terminal gives you and additional male terminal, and on and on) Purple & Pink/White can be seeing going into the same female terminal together, with all going to Key On using the 'add a terminal' connector.

So adding back Key On power to both isn't an issue, just wanted to know what the Pink/Wht one does. But...should be able to work that out now.

Thanks!

wexrocks · « **Reply #17 on:** December 11, 2012, 09:05:33 AM »

Ahh yes, the "add a terminal" connector. I cringe every time I find those. I always picture hitting a wake, one popping off and landing on one of the hundred or so ground terminals, and shorting out the whole boat in a smokey wire melted mess. I'm going with mounted terminal blocks on the scimitar. Those connectors worry me!

dorelse · « **Reply #18 on:** December 11, 2012, 09:25:29 AM »

Yeah, the plan is to add a fuse block.

kert0307 · « **Reply #19 on:** December 27, 2012, 12:18:41 PM »

Hopefully this isn't too late for you. Here is what is in the book I've got for dash wiring. I don't have a scanner at home so these are cell phone pics, but I think they should still work for you.

With thunderbolt ignition

Standard