1990 Dash Wiring

All,

Just wanted to give a quick updated on MY dash wiring project.

First off, special thanks to Nick for his awesome wiring diagram. I'm especially impressed that he took the time to figure it out after my personal look under the dash.

I didn't take any photos but just a few things to note:

My 1992 Sport did not have a "daisy chain" like was noted in Nick's post. Instead, it had the engine ground to a butt splice (it looked factory) which then went to two one large grouping of wires, each into a very large butt splice (again, it was factory). The first butt splice had all the grounds for the dash switch "ON" indicator lights (next to each C/B switch). Off of that splice, there was one jumper wire which went to the second large butt splice which had all the grounds for most of the instrument cluster.

Additionally, the ground wires for a couple smaller harnesses were tapped in to the instrument cluster grounds via butt splices.

A mechanic buddy of mine made a very nice buss bar and soldered some heavy duty jumpers between all the contacts on one side and made a 10 gauge "feeder wire" into that side, with a butt splice, where I attached the new ground wire from the engine (just like Nick did). I screwed the buss bar to the side panel under the dash to keep it secured. I then took the few odd rogue ground wires, snipped each, installed a ring terminal and fed it direct to that buss bar. I snipped the jumper between the two large butt splice junctions and fed each butt splice to the buss bar as well.

I started the boat and viola! No weird indications, no "jumps" when the lights were turned on and my voltmeter reads a steady 14 volts! (It never read above 10 v but I knew the alternator was doing it's job since I tested it with a voltmeter). Additionally, after running the boat all weekend, I discovered that my "warm operating temperature" issues were ground-related as well. Instead of running 160-180 (and close to 190-200 at times), it ran 140-160 (and never above) all weekend.

Lesson learned: These boats seem prone to bad ground issues. If you're chasing down some weird indications, start there first!

Again, thanks to Nick for his hard work, diagrams and post which inspired me to (finally) attack this, and to the rest of you who added in valuable information.

Mike,

That was my lame attempt at humor. Don't listen to a word I say.

(When you're done, you can do my boat).

Have a good weekend,

Dave

I don't see a problem with the ground wire if all you batteries are grounded to that spot and it's grounded to the motor. I do try and make my wiring easy for someone else to figure out so you might want to do the same for a future owner or someone working on it. The problem with wiring to the Perko switch would be that wire is connected straight to the battery and might not be fused. I've burnt up a couple of wiring harnesses on other things and it's a PITA to have to clean up and redo. I'm also not real clear how the newer boats are wired, so you might want to look over the diagrams before you start. I spent a few nights looking at the diagrams, and searching online before I decided what to do. Then I ran it buy a couple of engineers at work just to make sure my thinking was right. It's not that hard once you look at it a spend a little time figuring it out.   

I went and got some 10ga wire and a couple appropriate ring terminals at lunch. I am just going to do the ground first and see how that works. If that is not the complete solution, then I will run a wire from the perko, and definitely fuse it. I am 12v challenged, but not that much so.

thanks

Mike

OK. I have been putting off fixing my weak ground on my SAN for long enough. I have been stalling for 6 years.
I have a 2 ga. power and ground cable from my batteries to terminal blocks, and then they branch to my amplifiers. Is there any reason I cannot simply tag an 8 ga. ground wire from the ground block to my ignition, rather than going all the way back to the batteries? If I elect to run an additional power wire, I would come off the perko.

Sorry, still 12V challenged for the most part.

thanks

Daveinater wrote: confirm exactly where you ran that duplex from and to,

Load side of the main breaker for the + feed and engine block for the -.

Then, I prefer up to added terminal strips under the dash so you csn branch off from them instead of trying to tap into the existing daisy chains. The terminal strips also give you more room for future add-ons.

Solderless ring terminals for 8ga are not hard to find but I suggest getting the ones with the heat shrink insulation on them. Good old McMaster has them.

8ga, by # 10 stud ring terminals

Dave, if you do a google search for duplex at west marine, it comes up right away. Like I said earlier, I used 8ga, but if I did it again, I would use 10ga. 8ga connectors are hard to find and it's thick wire to work with. If you are ambitious or running high power amps or accessories, maybe 8 ga would make you feel better though.

TX Foilhead wrote: Duplex wire is just 2 wires that have a cover around both, it's handy because you only have to pull 1 thing. Like Eric said, it's like plumbing so I did both sides. After some discussion on other boards I decided to get my hot from the 50 amp breaker. Never saw a good explanation, but the general consensus was the 50 amp breaker protects the wiring to the dash should something go wrong with the alternator or the battery.

I second this. And at $3 a foot for wire, it saved me an extra $15 since the battery is under the rear seat in the sport. If you ran to the battery, I would add a fuse there but this means more connections.

Daveinater wrote: Hey TX, clarify what you mean by "duplex wire".

Dave,
"duplex" means two - Two wires in the same jacket. This saved him fro having to run single wires up for both the hot supply and the ground. Duplex in marine grade is available,

This is awesome - thanks! There is nothing like these posting boards to make me feel like a complete and total slacker. I had the exact same problem with my 90 Sport when I bought it 4 years ago. So after making sure I was really getting good voltage, I .....

... unscrewed the panel and disconnected the alarm. Definitely going to fix it one of these days...

Hey TX, clarify what you mean by "duplex wire". Did you just wire in a jumper parallel to the existing wire, to supplement it? What is the benefit to doing it that way vs. running an entirely new lead from the battery (or hot off the engine)?

I have a "Perko" selector switch (OFF-BATT 1- BATT 2 - ALL) that cuts off all power from the battery so I am good to go there.

Thanks Sebastian...that's what I was looking at. Brian tapped in to the daisy chain that fed his perfect pass, depth finder, etc. but I'm thinking I need to route my new ground right to the actual ground source under the dash, or bus bar if there is one. (I will drop the panel under the dash because I cant get my fat head in the storage compartment door). I want to supply the entire dash with a new ground wire since everything seems affected by whatever the problem is. I need to find where the stock ground wire (that attaches to the engine) goes under the dash. The wiring diagrams supplied in this thread should be helpful, but are cut off so I'll have to look again.

Perfect! Thanks and your post with photos was very helpful.

Question: where do the ground wires come together behind the dash...is it under the dash pod or behind the switch panels? I ran a new ground and power to my stereo direct from the battery Perko switch in the back because I had a hard time figuring out the actual "source points" for power and ground behind the dash. I'd love to give a new ground and, if needed, power source for the dash instruments but am not sure where to route the ground to supply the whole instrument panel with a new ground source. I'm thinking this is the best way to go because just about every indication is affected by the activation of running lights. Further, as I mentioned, the Voltage Meter always indicates well below 12V even tho the alternator is putting out good voltage. We pilots hate guages that lie!!    I'll start with the ground first and see if I get any headway.

Thanks again for the great post!

i know it always sounds goofy but i have to add and it relates, and it sure helps me diagnose things. if you view an electrical system as the same as hydraulic theories it helps. For instance, view the battry as a water tower, that is the storage or holding place (current/water) on that tower is, lets say 100 pipes to take the water to certain areas,(house/voltmeter) over time the pipe going to your house rusts and leaks and you have no pressure (this would be corrosion) or if your not getting full pressure at your shower head, quite possibly you would look at your on/off valve (switch) maybe it is clogged.
with the lower pressure you are demanding more pressure so you try and open the valve more and thus more flow trys to go thru the rusted pipe (amp draw) which in theory will heat the wire.
when you look at it this way it does help and I use the same identical theories to troubleshoot transmissions and engine oil pressure problems

Opps forgot to add that the 3 bank charger is because the way it's set up now I could do it as you say, but I'm mixing types of batteries so when the stereo bank is off it's also not paralleled for charging. 2 more batteries like the starting battery were $400, a couple of deep cycle batteries and another switch was less than $200 at Sam's.   The AGM deep cycle/ starting battery would last maybe a hour once I added the sub amp, but it was new last fall and I just hated to throw it away, but had no use for it anywhere else.   Over time I will eventually use the same types of batteries, hopefully that will be farther down the road like this.