Can someone walk me through wiring up gauages?

[Hannibal]

In replacing the top portion of my helm - I had to remove the guages and remove the wiring. I took plenty of pictures and even drew a diagram showing the wiring colors/paths. However, as it always the case, you don't know what details are truley most important until you realize you didn't include them in your notes. As such, I've discovered that my pics and sketch don't answer all my questions in getting the gauges back up and running.

I've googled and done some reading but everything seems much simpler than what I am dealing with.

For example:

While I have a pic of the particular gauge - it doesn't show me where each wire goes to/originates from. After tinkering with it a while, I understand that all the gauges are connected in line but it still doesn't work.

Couple of things I could use some better understanding of:

1) Where does the main power come from? I don't recall a main possitive line being connected to the gauges anywhere. And would I even want a full time power source to them? Shouldn't they be pulling power from the ignition source so that they are only on when the boat is on?

2) Where would the ignition source/hot be located? I have SOOOO many wires dead-ended behind the helm (likely from the previous owner's repower) that I am not sure what is what honestly. I have a cable cluster (following the main cable bundle) that is wrapped that includes a black/purple/white wire. Could this be it? Under a previous attempt, I had the purple wire feeding a + on the gauges with the black serving as ground. But I had no home for the white (and nothing on a pic or sketch showing it's connection point).

3) Off the main tachometer/all-in-one system check gauage, there are two posts and one harness. The harness is a no brainer. The lower post clearly says ground, however, the top post says nothing. And on the pics and the sketch - it had black wires running from it. But this either means someone got lazy with their colors or there is some other ground (and it's pulling power from the harness). When I turn the boat on - they system check lights up and beeps like it normally does. However, the tach doesn't work. Does it gets its information from the harness or am I missing a sending wire? Again, there are two posts - one I would assume as possitive/ignition, the other as ground. There is no "source/sending" post and I would assume it's getting it's power from the harness.

4) Off the main ground on the tach/all-in-one - there is a black/ground wire running to all the other (4) gauges. This to me serves as their ground contact. However, they are then looped/connected in series between them (a ground wire goes from gauge to gauge completing a loop). Is this normal or would it possibly create some kind of block? In other words, it's being grounded from two sources/wires. Sounds odd to me but I am no expert with electricity and it isn't working.

Now, in reading, I understand the basic theory of it all. Each gauge should have a power contact, a ground contact and a sending/info. contact. With my battery/volt gauge - there are only two. I am assuming this is because the possitive/power feed provides the gauge with the information it needs. However, even in simply hooking up the possitive/ground - it still doesn't move. And I have power to the main line and a ground bar right there. Then again, I didn't direct wire them to the gauge so maybe I need to .............

Maybe this is better solution ................

1) Where can I pick up the ignition/power source? What color is the wire?
2) Is the exposed black wire coming from the smaller wire cluster (with the purple, white wires) a ground? I would assume. Or should I directly run to the ground bar I mounted?
3) For my motor (if not standard) - Evinrude ....... what color are the sending wires for:
a. Temp.
b. RPM (if not done through the wire harness).
c. Voltage (if not done directly off the possitive feed).
d. Trim (never preiously connected).
e. Fuel level.

Any help would be appreciated. I am trying to finish up this project and avoid having to hit the marine mechanic.

 

[DaleH]

On OMC motors:

1) Where can I pick up the ignition/power source? What color is the wire?
This is typically a purple wire for +power ON whenever the key switch is ON.

2) Is the exposed black wire coming from the smaller wire cluster (with the purple, white wires) a ground? I would assume. Or should I directly run to the ground bar I mounted?
Black is ground, but note yellow has replaced black as the ground color when mixed with AC voltages, circa 2008 or so. Each gauge should be grounded.

Typically you wire up the 1st gauge in the cluster and then daisy chain the other needed wires to the other gauges.

A blue wire is GAUGE LIGHT, so if you follow this back, it should originate from your nav/anchor light switch, depending on how it is wired.

3) For my motor (if not standard) - Evinrude ....... what color are the sending wires for:
a. Temp. Depends on whomever set it up, but this should be a dedicated wire all the way up from the sender on the powerhead, top of the block starboard side. Follow this wire from the stern forward if you need to ...

b. RPM (if not done through the wire harness).
Gray wires on OMC is the tach signal.

c. Voltage (if not done directly off the positive feed).
As you said, the purple gives it the voltage.

d. Trim (never previously connected).
Usually a striped wire, maybe white with yellow or tan stripe or such, but this should come from the OB harness. Follow back from the controls if needed, where red was power to the trim switch, blue was 'sky' for trim up and green is 'grass' for trim down. Somewhere off that branch of the main OB harness should be 2 wires, a black and another striped wire for the trim signal.

e. Fuel level.
BIA standards have pink as the fuel sender wire, but FOLLOW IT BACK thru your run to be sure, as you should see it enter under the deck somewhere heading for the tank sender flange. Fuel senders work off resistance, not voltage per se, so you DO NOT want to apply power to that tank! If in doubt, please call in a pro!

Going on, you are most correct, each gauge needs:

Purple - So the gauge is powered when the ignition is turned ON

Blue - Gauge light for nighttime use

Ground - Complete the circuit

Sender - See above

NOTE - Tach also needs the gray wire. Typically on an OMC harness you will find a branch that has the gray, purple, and black as one lead, with a connector, or just ends if someone didn't use OEM connections.

If needed to rewire, you could fire up the tach and then add the purple (power) and black (ground) to all of the other gauges. As I said, the blue wire for gauge lights should come from your power switch for nav/anchor lights.

Then the senders would be needed ... so read all of this and GO SLOW through that rat's nest. A label maker would have been invaluable here ...

 

[Hannibal]

NOTE - Tach also needs the gray wire. Typically on an OMC harness you will find a branch that has the gray, purple, and black as one lead, with a connector, or just ends if someone didn't use OEM connections.

Ahh, this is the smaller wiring cluster I was referring to above. Where I said white - I am sure it is gray.

Thanks Dale. While not absolute quite yet - I am definately futher along. I really think I just may as well cut new wires and redo it from scratch. Just have to find the correct sending units.

One question though - when discussing the trim gauge - are there more than one signal wire? You said green/grass and blue/sky (for direction). Would both need to be attached to the sending post?

Also (just a guess here) that the where most connections are post connections with nuts - each gauge has a blade connection that was originally connected to a lead blue wire (don't know where it originated) but then switched to a gray. I am guessing this is the connection/wiring for the lighting. I should be able to tap into the wire for the nav lights as my switch panel is right there.

 

[DaleH]

Those TRIM colors are leads to the trim switch and/or to trim motor. Was trying to educate you and others on trim color convention. These do not connect to any gages. Trim sender leads are as stated, a striped wire.

Many people use ANY color they have handy when making connections, so the blue ones from gauge LIGHTS might switch to gray, fo follow it and see where it leads, if anywhere. If no where, that would go to your choice of anchor or nav (running) light poles, but not both. I personally put my gauge light to the nav lights, so when drift fishing at night, I'll can put just the masthead/all-around light on ... so others can see me. But I don't need to consume any more power than that, since the OB is typically off too ...

 

[Hannibal]

Dale,

I had partial success last night. I stripped off all the old wires and created new leads. In the process, I got the fuel gauage to activiate and found the old trim tab wire (never worked previously). With that, it appears I have to calibrate the switch/gauge as it's currently in the up position when the motor is down. But it moves when I activate the switch ..... that's a plus.

I am still not getting a reading on the voltage gauage even though I have the power being fed by the purple wire (which is connected in series to everything else ......... only power source). Aside from that, there is only a ground wire which is the only ground in the series. Point being, if other gauges are working (well some) in sense stating the power/ground are sufficient - why wouldn't the voltage read?

I am also not getting a temp reading on the temp gauage. Refering back to my sketch and referring to the color codes - the brown wire is the sending wire for temp. It previously worked and all I did was disconnect and reconnect. However, after running the motor for 10 minutes, it didn't budge.

Lastly, I am still not getting signal for the RPM's. I would think that the harness connection to the tach (from the bundle) would provide this information (there is a gray wire there). However, with it not working, I searched all over for a gray wire serving this purpose. I couldn't find one. I found several gray wires that were utilized in other wiring operations (hell, one is tied in with my navigation lights oddly enough and controls the white all-around light on top of my roof).

In referring back to the original pic of the back of my tach (see below) - I don't see any gray wires. My sketch didn't show any gray wires. I am not sure where this wire is or even where it would attach to. Referencing the below pic - the bottom post is marked as ground. With there being only two posts for connection - I would have assumed that the top post is Ingition/Power. This is how I have it rigged currently (and it's getting power) .... a little light can be seen on the back of the gauge when connected. Audible alarm can be heard when disconnecting/reconnecting it.

To me - this leaves no place for any gray wire as a sending wire ....... unless I am supposed to connect it to the power/ignition post. I am confused.

Any ideas ..................

I am getting REALLY frustrated with all this and am quickly considering taking it to the marina to get done. I am running out of patience and running out of kitchen passes from the wifey. And I still have the lower unit oil to swap, new plugs to put in, replace all the filters, etc. Though, I think that should all be easy/quick to accomplish.

Oh yeah - and I still have to clean the thing!

 

[DaleH]

I'd forget about that "forrest" and would tackle it one "tree" at a time, starting with the tach.

I have a spare OMC tach I could send you, if you pay shipping. I also have for sale the digital model, used to test, but NEVER installed. It is THE most accurate tach on the market. $30.

Somewhere in that OB Harness coming up from the stern you should find the tach wire bundle of 3-wires, gray, purple, and black.

I also have spare OB harnesses, with Deutsch or Amphenol connections.

I'll have to check my Volt gauge wiring this SUN and I'll take some photos.

NOTE, to me, you shouldn't see the light until the gauge ligt switch is powered, which makes me think you're using the wrong terminals. PLEASE go to the Teleflex website for marine gauges and download their instrument installation manuals for he gauges you have, as Teleflex are are direct, in not OEM gauge for those motors.

Take a breath, go slow ... don't lose patience ...we'll get you there!

 

[Hannibal]

NOTE, to me, you shouldn't see the light until the gauge ligt switch is powered, which makes me think you're using the wrong terminals.

PLEASE go to the Teleflex website for marine gauges and download their instrument installation manuals for he gauges you have, as Teleflex are are direct, in not OEM gauge for those motors.

Dale,

There are only two posts on tack along with the harness. One is clearly labeled GROUND but the other post is not labeled at all. In the pic above - the bottom post is ground and the top post is not labeled. As you can see on the post - there is a mix of wires attached to it. Some are black and per the sketch I drew up - went to ground locations. There is a blue/white (light?) attached to it and another wire that WAS white with a black stripe (I believe) but it was cut after about 6" (not connected to anything).

When I wired it up the last time - I used the top post as the Ignition/Power and had it wired in line with the other I/P lines (purple). So when I turned on the ignition - a light would appear in the back (it was daylight so I am not sure about the front illumination). When I turned the key to off - no light.

So I am not sure of it's purpose. If it's a light post and not a power post - where is power coming from? There are only two posts and one is definately ground. Doesn't make sense.

Also, regarding your comment concerning the RPM - I had one small wire bundle (wrapped) that house a black/purple/tan with stripe. I used the purple to be my source wire for the first gauge of the series, the black was the ground to my first gauge of the series (voltage) and I ran the tan w/ stripe to the trim gauage as the sending wire. The needle moved (first time ever) and settled just south of "UP" (even though motor is trimmed down). I am assuming I did this right.

But more to the point - I didn't see any other smaller bundles set up like this with the exception of one. Coming out of a smaller bundle (again, wrapped) was a purple/black and grey wire combo. However, the purple and black wires were cut and the gray was connected directly to the existing ground bar behind the helm. It had been there for a while as it had been coated with a black corrosion inhibitor. So I am guessing that wouldn't be my sending wire.

 

[Hannibal]

Dale - I searched their site. I am not seeing anything regarding installing gauges. I checked their install manuals and technical support and nothing comes up. You have a link by chance?

 

[DaleH]

Dale - I searched their site. I am not seeing anything regarding installing gauges. I checked their install manuals and technical support and nothing comes up. You have a link by chance?

Volt Meters: Per the Teleflex FAQ website: http://www.teleflexmarine.com/support-2 ... mentation/
A voltmeter can provide the operator more information. Condition of the battery at idle or with the engine off, is the battery being charged when the engine is running above idle, is the voltage regulator set correctly.
Additionally, the voltmeter is easy to wire. Install in dash, connect "I" to ignition switch or any good-switched positive wire from the battery, and connect "G" to common ground. The voltmeter is in operation giving information on the electrical system. Wire size can be 14 to 18 gage.

Teleflex Technical Support Call them for installation (as in HOOK UP, not cutting the hole in the dash)
Contact Number 1-877-663-8396, ask for Instrumentation help

Hours of Operation: Monday – Friday 7:30 am – 4:30 pm CST

Areas of Expertise:
• Sierra Engine and Drive Parts
• Instruments and Gauges
• Shields Hose
• Switches and Electrical Products

 

[Hannibal]

Problem was determined to be two bad gauges. The original Evinrude RPM/System Check gauge was faulty. Had to buy a replacement. Works fine now. Still waiting on a matching voltage gauge which should be in this week. The wiring mess the original owner left me made no sense but it's all been cleaned up/simplified. Even have seperate control for the backlighting (tied to the nav lights ..... thanks to whomever recommended this).

Figured out why I was seeing light (reference is made to an earlier post above). I had the ingition wire tied into the tach's light post. On the old tach (and the new one) - power and signal for the tach/system check is supplied by the harness. Hence no seperate posts for power/ignition. The only two posts on the back serve as ground and for backlighting. When I was applying power to the lighting post - I was getting light ......... but full time (with the ignition engaged). Now all the gauges are tied in series for ignition but skip the tach. It is series'd in for ground and backlighting though. Signal and power is coming from the wiring harness.

Will post pics of the updates once I get the boat cleaned up.

 

[DaleH]

The "pain" you have felt through this ordeal will be replaced as you go forth by "confidence and experience" that you now know more about your boat and it's rigging.

Glad that tip about the separate switch for gauge lights worked for you. If you want to get a tad fancy, I 'paint' my gauge bulbs with a red sharpie marker so they don't impede my night vision.