Let's talk about 12v electircal stuff...

[Tony Payne]

ok, I understand enough to be dangerous... but let's talk about a 12v system.



Most depthfinders have the ability to display current "voltage"...



I would expect that under normal circumstances it should read roughly 12v (slightly higher when the big motor is on).



Now, when I turn on accessories (livewell pumps, the other fishfinder, running lights, etc)..



Should I see a voltage drop? (on the order or 3 for the running lights, 1.5 for each pump, etc).



When the items are turned off, the voltage returns to normal (or thereabouts).



What does this tell me, if anything?

 

[Jim B]

You shouldnt see that much of a drop off. What you have going on is a current problem. What happens when the current is limited is you get some voltage drop. I had the exact same issue with my 882 and it was caused by the main power wire from the battery being way too small for the amperage load the accessories tried to pull mine was a 18ga wire. My fishfinders voltage reading would drop from 12.5 volts to 10 if i turned on my livewell pumps with one finder running. I ended up replacing the main wire from the batery to the switch and from the switch to the fuse panel with a 10ga wire and i also replaced the main ground form the fuse panel to the battery with 10ga. That totally fixed the issue for me. I now can run both my ff's, both well pumps, my radio and my flasher and only drop .2 volts as shown on the fish finder. Id bet you are having the same problem. Does th evoltage drop more the more you run something like the pumps? Mine would and when i grapped the power wire near the battery it would get warm and get warmer as things contnued to run. Poor design if you ask me.

 

[Tony Payne]

yep... that's what I'm talking about...



I see upwards of 3-4 volts if I turn on both the anchor/running lights, avg of 1.5 volts for each pump...



Actually sucked the battery dead one time when I plugged in the Q-Beam.



What I wasnt sure of is if this meant I had to track down individual stuff, or if it was as 'simple' as you say. I was worried it to be more of a corrosion issue that would be to each connection.



I take it the 'large' wires are probably to the motor, while the 2 smaller wires are going to the fuse panel/switch?



next question is... Do it myself or take it to the dealer?

 

[Tony Payne]

(dealer question is because this is my 'new' 911... I would think this is a warranty issue)

 

[Bruce Freeman]

Get a volt meter and check voltage at the battery with everything on and compare the 2 readings. If there is a big differance between the 2 reading the problem is in the wireing or connections, if the reading are the same then it could be a weak battery?



BF

 

[Jim B]

On my boat i had one small 18ga wire going from the battery to the main power switch. Its the one with the fuse in it. There are also two ground wires one from the panel and one from the fuel level sender. The problem i had was things like my finders shutting off due to low voltage. I originally thought the problem was battery related so i upgraded it to a group27 sized start/deep cycle with the same results. When i dug in deeper i realised something i overlooked. Over the 10' or so span that that one little 18ga wire runs its only good for about 5 amps at 12 volts. The two livewell pumps alone draw more then that! I put my ammeter on it and with all my accessories running( 2 well pumps, bilge, radio, flasher, 2ff, gps) i was pulling closer to 15. Basically that 18ga wire was overloaded and a really dumb design. At 10' 12 ga will carry 15 amps but i decided to err on the big side and went with 10 because it will carry 20 amps and isnt much more expensive.



I would think its a DIY type job. I seriously doubt the dealer will modify trackers design( no matter how bad it is) under warranty. Its not a hard job to do either. All you need is the wire(power and ground), some loom to wrap it,zip ties, a fuse holder, a butt conenctor, some female blade connectors for the switch, some big ring connectors for the battery and a small one for the fuse panel. From there just replace whats there or piggyback it. I left all the factory wire intact just tied it back and disconnected it.



As far as the dead battery goes that might be that the battery isnt big enough to run the light for a long period. When i first put the radio in mine i had the standard group24 start battery and it didnt have enough reserve capacity to run my radio for more then a few hours( just like a car) before it was dead. With the 27 deep cycle/start i can run it all day and not even have to worry about it. A 24 deep cycle/start would work too but since i had the extra room i went bigger.

 

[Tony Payne]

Thanks Jim...



Sounds like a project... Think I'm gonna run either 8 or 10... hardest part is weaving the wires thru the center console thing.



The battery is almost new, it is a group 27 but is just a cranking battery.



Thanks for the help!

 

[Texas Transplant]

On my new HBird, the wiring for power is very small. It see's minor flucations all the time. If I had a beefier wire for power, it wouldn't be as affected.



Tex

 

[TrepMan]

I thought we you wanted to talk about what 12 volt stuff we run on the boat!! I just got a cig plug for my new floating crappie light instead of trying to hit the battery with clips!!