Electrical issue question

oh... the " stuff laying around"...so my buddy's skiff.. (major mfgr) a 18' job.. well apparently they have wiring harness and plumbing stuff (live well,bilge pump ECT) premade for several size boats and if there is a few feet left over they just coil it up and stuff it ? somewhere?? ... scuppers draining into the bilge have to let the water get by the coiled up rolls of "stuff"... UGLY..
As long as you can WALK home no prob relying on someone else to do the 'lectric right.

Sea Antsy said:

oh... the " stuff laying around"...so my buddy's skiff.. (major mfgr) a 18' job.. well apparently they have wiring harness and plumbing stuff (live well,bilge pump ECT) premade for several size boats and if there is a few feet left over they just coil it up and stuff it ? somewhere?? ... scuppers draining into the bilge have to let the water get by the coiled up rolls of "stuff"... UGLY..
As long as you can WALK home no prob relying on someone else to do the 'lectric right.

Click to expand...

I wouldn’t hesitate to name the manufacturer if saw this type of poor workmanship. This kind of bs deserves some bad reviews.

CS

Just an update to my electrical issue. I suspected the power wire going to the dash being the culprit, so started the chase. Turns out that power cable turns into a wiring harness with 12 other leads going to various things in the dash. Switches in the dash all have breakers added to them. The Lawrence unit has it's own power cable from the house battery. Totally lost in the ball of wires for this old boy....so I set up the volt meter to show the 12v at the bare hull and started disconnecting wires one at a time to see if any changes showed up. Nothing...nothing changed but I did find a couple skeptical things. A timer switch had been added for the aerator system on live wells I don't use so that was removed and wires removed and capped. Also the SS radio had some questionable connections and I never use it and always made a noise when power cables were connected even with radio off. Not sure why but after removing those two items and finding O changes when connecting/ unconnecting alk the other wires, I tried just going back to the beginning and starting over. I still get the 12v reading when I ground to the bare hull but in the past 48 hrs there has been NO drop in my battery voltage. So waiting more time to see what happens. No funny noises when leads are connected and disconnected, so that might be a plus, so far no variable voltage readings, and everything works !! Can't even say for sure that the 12v reading on the hull hasn't always been there, never checked it before until this battery drain issue came about. While I did learn some new things, electricity is still a foreign subject to me. Many thanks for all the responses and suggestions, gonna give it a little time and monitor everything frequently to see if anything changes.

You guys are making me nervous. My Crestliner has some iffy looking wiring. Maybe I should just start over. What I find interesting is most of the wires are connected in a wide ribbon. Must be at least 10 wires. Factory?

On our 2022 SunTracker, had to access behind the fuse box to pull transducer cable and when I ran the Vessel View cable. It is quite the birds nest of wire! On the G3, a bit neater layout, but far from pristine.

[/QUOTE]

airshot said:

Just an update to my electrical issue. I suspected the power wire going to the dash being the culprit, so started the chase.

Click to expand...

One item, I think everyone will agree on. The positive cable should not be tied to the hull.
So when you have a chance, I would :
Disconnect the + wire on house battery, set meter to continuity, set ohm setting to highest setting (2000k). Check continuity between + house battery cable and hull.

Any reading other than open (infinite resistance) could be an issue.

One item, I think everyone will agree on. The positive cable should not be tied to the hull.
So when you have a chance, I would :
Disconnect the + wire on house battery, set meter to continuity, set ohm setting to highest setting (2000k). Check continuity between + house battery cable and hull.

Any reading other than open (infinite resistance) could be an issue.
[/QUOTE]
Thank you for that detailed description !! Makes it much easier for me to figure what to do...

airshot said:

One item, I think everyone will agree on. The positive cable should not be tied to the hull.
So when you have a chance, I would :
Disconnect the + wire on house battery, set meter to continuity, set ohm setting to highest setting (2000k). Check continuity between + house battery cable and hull.

Any reading other than open (infinite resistance) could be an issue.

Click to expand...

Thank you for that detailed description !! Makes it much easier for me to figure what to do...
[/QUOTE]

Do the negative side resistance test, too. The side with the lower resistance should be what to focus on.

Then remove all wires to that post and check each individually for continuity to hull. Don’t stop when you find one, in the off chance you have more than one issue.

At this point you will know what circuit(s) are involved. At that point let us know which side and what circuits they are and can provide a methodical way to isolate further.

FuzzyGrub said:

Thank you for that detailed description !! Makes it much easier for me to figure what to do...

Click to expand...

Do the negative side resistance test, too. The side with the lower resistance should be what to focus on.

Then remove all wires to that post and check each individually for continuity to hull. Don’t stop when you find one, in the off chance you have more than one issue.

At this point you will know what circuit(s) are involved. At that point let us know which side and what circuits they are and can provide a methodical way to isolate further.
[/QUOTE]
After thinking about this, I already did this test. It showed the wires carrying power to the dash thru the wiring harness from the factory as the culprit. These power wires tie into the main wiring harness for the boat ( not engine) . Where these connect is buried deep and will require a major disassembly of the starboard side of the boat, might have to wait until winter. In the mean time I went thru all the dash wires, unplugging and plugging in to see if there was any difference in the reading....none...but your right it may be more than one. In the mean time, after removing a suspect timer switch, there has been no battery drain after almost 4 days. The switch was mounted where my knee bumped it on frequently. Not saying the problem is fixed, if there is a problem, but, due to the season being here, I am going to monitor things very close and get thru this season if I can. My boat is stored in my barn so close monitoring is not a problem. Many thanks for all the help so far....keeping my fingers crossed !!

At this point you have probably found the parasitic device and think having the hull tied to ground is better than having +12V on it. Myself, don’t really know what the consequences are of that. Outside of a positive terminal falls off and touches the hull it will be a direct short. Fuse should blow. Some tin boats are tied to ground thru engine mounting. Maybe Dale knows if it is a safety issue vs a noise or corrosion one.

Sorry if I missed where you did a continuity test on the ground wire from the console. When you disassembled the 12 devices at the console, that test should have shown if it was the ground going back to the battery or one or more of the devices. If the ground wire is hard to get to, sometimes it easier just to snake another wire thru.

Sometimes it is very hard to understand the electrical layout from a verbal description. A hand drawn diagram can help tremendously. When you get back to it, let us know, will do what we can to help.
.

FuzzyGrub said:

At this point you have probably found the parasitic device and think having the hull tied to ground is better than having +12V on it. Myself, don’t really know what the consequences are of that.

Click to expand...

Some really good points.

Just some gee wiz information. It's OK to ground/bond to the hull, you just can't use the hull as a conductor. Should be a single point at the engine.

The hull is considered ground or 0v poential. It becomes earth ground when in contact with the earth.

So, fuse should have blown.

The reason, I would recomend a contunity check of + cable at high resistance is a 10M ohm short to ground may not blow fuses, but still show a voltage. Not all ohm meters are capable of reading high resistance and can give misleading readings.

InSaneFisherMan said:

Some really good points.

Just some gee wiz information. It's OK to ground/bond to the hull, you just can't use the hull as a conductor. Should be a single point at the engine.

The hull is considered ground or 0v poential. It becomes earth ground when in contact with the earth.

So, fuse should have blown.

The reason, I would recomend a contunity check of + cable at high resistance is a 10M ohm short to ground may not blow fuses, but still show a voltage. Not all ohm meters are capable of reading high resistance and can give misleading readings.

Click to expand...

Not electrically smart enough to know if mine will do that or not. From my reading and what little I understand, the bonding theory might be it. Talked to a service tech and our local BassPro shop, and he said it was not unusual to get a 12 reading when touching bare hull. There are no wires connected to the hull that I can find, everything has a neg wire to battery, so....with my very limited knowledge, I am thinking the bonding from the motor being bolted to the transom. At least the draw down issue has been resolved. Again many thanks !

InSaneFisherMan said:

Some really good points.

Just some gee wiz information. It's OK to ground/bond to the hull, you just can't use the hull as a conductor. Should be a single point at the engine.

The hull is considered ground or 0v poential. It becomes earth ground when in contact with the earth.

So, fuse should have blown.

The reason, I would recomend a contunity check of + cable at high resistance is a 10M ohm short to ground may not blow fuses, but still show a voltage. Not all ohm meters are capable of reading high resistance and can give misleading readings.

Click to expand...

Not sure mine is capable of that...

airshot said:

Talked to a service tech and our local BassPro shop, and he said it was not unusual to get a 12 reading when touching bare hull.

Click to expand...

With respect to what? (i.e. what are you measuring against?)
red meter lead to hull
black meter lead to ???

old_fart said:

With respect to what? (i.e. what are you measuring against?)
red meter lead to hull
black meter lead to ???

Click to expand...

Battery to bare hull with vom

InSaneFisherMan said:

Some really good points.

Just some gee wiz information. It's OK to ground/bond to the hull, you just can't use the hull as a conductor. Should be a single point at the engine.

The hull is considered ground or 0v poential. It becomes earth ground when in contact with the earth.

So, fuse should have blown.

The reason, I would recomend a contunity check of + cable at high resistance is a 10M ohm short to ground may not blow fuses, but still show a voltage. Not all ohm meters are capable of reading high resistance and can give misleading readings.

Click to expand...

You really have no choice. Assuming the outboard is solidly bolted to the transom, ground will always find a way from the engine block to the hull. Many outboards even have ground leads that tie each component of them together if they're isolated in rubber.

airshot said:

Also the SS radio had some questionable connections and I never use it and always made a noise when power cables were connected even with radio off.

Click to expand...

That's the most likely culprit right there.

For something like this, I would recommend placing an ammeter in series and begin disconnecting the circuit in chunks. Pull the power feed for any accessories off the battery and isolate the outboard. If the draw goes away, disconnect the outboard and reconnect the accessory feed. If the draw is back, begin cutting power to each group/fuse panel or individual accessory. Eventually you will find a circuit that is drawing power, from there it is just a matter of checking each component on that circuit.

I've got the same thing going on with the 50hp Evinrude that I put on my boat this winter. Never had this issue with the previous motors, but it will kill the battery sitting overnight. It has no issues otherwise, charges and runs just fine. I suspect a bad voltage regulator but I haven't tried to isolate it yet.

Early in the discussion, it was said that this house battery was completely isolated from the starting battery, and hence not grounded thru motor. In the AC world, having two or more ground connections causes ground loops which cause noise. I don't know if that makes a problem in the 12V DC world.

The only thing I can add at this time is there is a wire from the metal plate on the plastic fuel tank that does attach to the aluminum on the transom. Assuming a ground for static purposes when filling....?