Fish finder/ GPS turns off when starting engine

[Blaugrana]

The bottom right corner of the fuse block is a negative bus. what feeds that? Is it a jumper from the negative bus in the other picture or does the neg from the battery go there?
Is it fed with the same gauge wire as the positive?
https://www.greatgrady.com/attachments/22677be9-1d96-49a1-8673-324bb4631057-jpeg.14780/


Those blue green wires are fuel tank & bilge pump grounds

I'll double check both. I believe the negative on the fuse just goes to the negative bus, but will confirm that.

Were consolidated negative bus and fuse not around in the early 2000s? I am looking at buying a new fuse panel and was curious if I should replace both (negative bus as well) or just the fuse panel. If replacing both, should I just buy an integrated one that includes all of the negatives. I reached out to Grady this morning to see what they use on their new boats.

 

[Blaugrana]

FWIW.
I was having the same type voltage drop to my older garmin C/P. it would cause the display to flicker but not go off.
Could touch the wire at the Fuse panel and would work fine for awhile.
I took the Fuse Panel out, disassembled it cleaned the contacts , replaced the connector on the wire from the C/P.
Still had the same problem, when the screen started flickering the displayed voltage would show in the 10 volt area.
I could reach down touch the connector at the fuse panel and voltage would go back to battery voltage.
Replaced the fuse panel and have no more trouble.

I never would have believed it after cleaning the old one as good as I did. Made a believer out of me.

What panel did you go with? Blue Sea Systems? Panel only? Or Negative also?

 

[SkunkBoat]

FWIW.
I was having the same type voltage drop to my older garmin C/P. it would cause the display to flicker but not go off.
Could touch the wire at the Fuse panel and would work fine for awhile.
I took the Fuse Panel out, disassembled it cleaned the contacts , replaced the connector on the wire from the C/P.
Still had the same problem, when the screen started flickering the displayed voltage would show in the 10 volt area.
I could reach down touch the connector at the fuse panel and voltage would go back to battery voltage.
Replaced the fuse panel and have no more trouble.

I never would have believed it after cleaning the old one as good as I did. Made a believer out of me.

I have had two of the ATO type fuse panels go bad. They were basically "cooked". Plastic melted or crumbling.
One was on an old Welcraft and the other was on my Grady 265 up in the electronics box.
When the blade fuses get a "green" corroded connection it heats up and cooks the plastic. Then the plastic is no longer an insulator.

I would be a good idea to remve the panel and look for bubbles or burns on the backside

 

[Sparkdog118]

First thing I would do is replace the fuse box. Cut off all the wire ends and crimp on new connectors. That style box has lots of corrosion issues. Doesn’t take much corrosion to make the box loose voltage and have problems. Cleaning this style box has a very low success rate. I have replaced a lot of those style boxes. I would also change the battery switch for piece of mind.

 

[Sparkdog118]

Blue sea is good. The integrated ones are great. Make sure all wires have new connectors so the corrosion fungus doesn’t start growing on your new box. Spray the whole box and connectors with corrosion block when you are finished assembling. Also check the nuts on the battery are super tight with a ratchet.

 

[Sparkdog118]

Blue Sea Systems ST Blade ATO/ATC Fuse Blocks https://www.amazon.com/dp/B001P6FTHC/ref=cm_sw_r_cp_api_i_GqQfFb9AMF8XK

 

[seasick]

Replacing those blocks may be a good idea down the road but a bad block would not explain the extremely low voltage at the dash on the first test results. If the block was bad, the dash voltage would be very low in both cases and it wasn't. I would concentrate my investigation in the battery compartment area first. It really looks like a common ground (negative) cable issue with the batteries.

There is an easy way to see if that cable is a problem. You might need a helper. Measure the voltage between the two battery negative terminals. Yes, the two negative terminals. With nothing on, it should be close to zero volts. Now crank the motor on one battery at a time and note the measurement. If I am correct about that bridging cable, there will be a significant voltage measurement when cranking and it will be different for each battery.

 

[Blaugrana]

T

Blue Sea Systems ST Blade ATO/ATC Fuse Blocks https://www.amazon.com/dp/B001P6FTHC/ref=cm_sw_r_cp_api_i_GqQfFb9AMF8XK

Thanks - I’ll purchase this now and see if it’s needed to fix the issue. Worst case, I’ll replace it regardless when I take the boat out in offseason.

 

[Blaugrana]

Replacing those blocks may be a good idea down the road but a bad block would not explain the extremely low voltage at the dash on the first test results. If the block was bad, the dash voltage would be very low in both cases and it wasn't. I would concentrate my investigation in the battery compartment area first. It really looks like a common ground (negative) cable issue with the batteries.

There is an easy way to see if that cable is a problem. You might need a helper. Measure the voltage between the two battery negative terminals. Yes, the two negative terminals. With nothing on, it should be close to zero volts. Now crank the motor on one battery at a time and note the measurement. If I am correct about that bridging cable, there will be a significant voltage measurement when cranking and it will be different for each battery.

Thanks...I’ll give this a try.


I’m going to clean up all terminals first.

Should I attempt to troubleshoot the bridging cable or just remove it and use battery #1 only to see if the same drop to 8.8 exists?

I’ll fill everyone in by this weekend as I should be by the boat again.

 

[seasick]

Thanks...I’ll give this a try.


I’m going to clean up all terminals first.

Should I attempt to troubleshoot the bridging cable or just remove it and use battery #1 only to see if the same drop to 8.8 exists?

I’ll fill everyone in by this weekend as I should be by the boat again.

Clean up the terminals first and check the cable lugs to make sure they aren't loose. Then I would do the voltage across the bridging cable next

 

[Blaugrana]

For future reference ...

So, before doing any further tests, I cleaned up all of the terminals on my older batter that was considered battery #1. Some of the terminals were definitely aged, but I was able to get them looking new again. After doing this, I ended up running some voltage tests with results below...

- Battery w/ key off = 12.68v
- Battery w/ key on = 12.58v
- Starter Relay, not cranking = 12.55v
- Starter Motor, cranking = ~7.9v
- Starter Relay, cranking = ~7.6v
- Battery Positive to battery term on relay, not cranking = 0v
- Battery Positive to battery term on relay, cranking = 1.7v (2v for battery #2)

I ended up taking it to the marina who noticed that with the switch on both batteries, there was no issue. They inspected the switch and cables with no concerns. They believe the new starter motor and relay might be pulling more voltage than necessary.

They ended up recommending what SkunkBoat highlighted earlier on with a dedicated starter and house battery. They switched my battery switch around so that my bilge and all go to my new this season house battery (#2) and then installed a new starter battery (1000amps) to #1.

When starting, none of my electronics go off and I notice that the Yamaha battery gauge doesn't go below 11.5 or so when starting...The Garmin does note low voltage but the warning says 11.4v or so

Quick Question: For those that have the old Guest Battery Switch and a starter battery, do you switch to both while running and the house while drifting? That's what I was told to do and seems to be ok, but I'm just nervous about not getting enough charge to my Starter. As an fyi, it's definitely a pain to switch now when I start drifting and then again to start the engine because my battery switch is not inside by the battery. Curious if anyone has their exposed and not tucked away under a seating location.

 

[SkunkBoat]

In my opinion you should get an ACR so that both batteries always charge and you NEVER change the switch off of the 1 position.
You could do the same with an Aux charging wire from you Yamaha to the #2 battery.

 

[Blaugrana]

In my opinion you should get an ACR so that both batteries always charge and you NEVER change the switch off of the 1 position.
You could do the same with an Aux charging wire from you Yamaha to the #2 battery.

What about with drifting? Would I just leave on the starting battery if I had an ACR?

 

[SkunkBoat]

What about with drifting? Would I just leave on the starting battery if I had an ACR?

As you have already said, you have a House battery #2 and a starting battery #1.
You said you already connnected the 12v panel to the House battery instead of the Motor start wire. (it should be thru a breaker switch or a breaker and a new On/Off switch)
Your panel will always be powered by the House battery even when you are on position #1.
In other words, the existing battery switch only effects which battery or batteries are starting the motor.(you would leave it on #1)

The ACR will connect the two batteries for charging via the motor start cable but isolate them so that the House battery does not share in starting the motor.
Switching from #1 defeats the purpose of the ACR.

The Blue Seas website has circuit diagrams for single motor/dual battery configs using their ACR.

IMO (a lot of guys here may think otherwise) The idea of switching back & forth in order to charge batteries is just stupid. Running on the Both position for any reason other than emergency starting the motor when both batteries are weak is just stupid.

Also, I ran a single engine 20fter for 18 years using a single group 27 dual purpose marine battery. One battery, no switches, no problems. ran electronics and lights at night.

 

[SkunkBoat]

Overcoming_Dropout_of_House_Electronics_during_Engine_Starting

 

[Blaugrana]

Overcoming_Dropout_of_House_Electronics_during_Engine_Starting

Thanks!!!