Some possible electrical issues after replacing battery

[Benny67]

But none of it means anything unless you have good solid connections throughout the circuit...

 

[Benny67]

Start your engine, get a long test lead and measure the voltage between the positive post of the battery and the positive post at your console fuse panel. Then do the same for negative to negative. You should be getting very low voltage numbers and each side should be around the same. If you don't and/or either number is more than 0.5V, you need to identify where the drop is.

Huh?

In reference to what?

If you put a meter between + on the battery and+ on the gauge you won't see any voltage because there is not going to be current flow. Both leads are at the same potential

A simple resistance check is going to give you the information you need.

 

[Benny67]

This is getting WAY out of hand....I am gonna step back and watch at this point.

You know what they say...too many cooks...

 

[wellcraft-classic210]

Gents
We are all trying to help here and their can be many ways to accomplish the same thing;

What Bruce B is proposing is a simple and effective method to look for a voltage drop on the supply and GND lines.

-- A very key point is that this is while MORE CURRENT is flowing than a multi-meter will produce in the ohms setting and therefore a slightly different test that could pinpoint an issue that an ohmmeter would miss.

Reason
-- Connectors can sometimes have a very small area that makes good contact when they are acting up // but a voltage drop will occur when under load due to limited area with good contact.

 

[bruceb58]

If you put a meter between + on the battery and+ on the gauge you won't see any voltage because there is not going to be current flow. Both leads are at the same potential

There is current flowing between the battery positive terminal and the fuse panel if you turn on the ignition. In a perfect world, it should be the same. If there is any resistance in any of the connections(and there will be)you will measure the voltage drop.

Resistance checks are pretty much useless since there are so many branches that can effect the measurement. Also, the measurement will be so tiny that any error caused by the meter will throw you off. Always better to measure voltage drop with current flowing.

 

[Benny67]

Bruceb58

I disagree...advice like this isn't helping anyone because you are basically saying your way or the highway.

Your technique can work. However, your statement about resistance checks being useless is just plain bad advice based on ego.

You do realize the entire circuit is based on a varying resistance don't you?

Anyway...I'm basically going back on my word of saying I'm pulling my horse out of this race.

Good luck to the OP

 

[Benny67]

I forgot to add that the multimeter the guy is probably using is most likely $10 cheapie

​the difference in potential between two points of reference could be way off in actual values...basically making the information inacurrate.

500 milivolts registered on a hobbyists toolkit meter I would suspect could be off by as much as 20%

Based on your theory, 20% error would give you garbage data to solve the problem effectively.

And also based on the OP's experience in electronic troubleshooting (please...no offense meant,I'm basing it on your explanation of the problem ) I don't think the path you discribed to take is going to solve his problem.

Just a few factor to add to the debate. ..again, good luck to the OP

 

[Grub54891]

Just curios here, did you use a pipe dope type sealer on the threads of the sender? If so, it will isolate the sender from the ground, and will give bad readings. They are put in with no sealer, so they make good contact to ground. Just something rolling in my mind....

 

[trentbt1]

Holy crap... appreciate the help, but the tester I have is certainly not a "cheapie". I took the boat out all weekend again and did notice a few things that popped into mind. When I take it down to the lake to start it up the first time, I flip on the ignition and the exhaust opens up with authority and alarm sounds. I do notice while the boat is not running but with switch on, the gauges do not move when I operate the trim, exhaust switch etc. when I start it and the boat is idling, that's when I notice the gauges going down when I operate switches/trim. It also acts like it wants to kill the boat at times. After running WO for awhile, I shut it down and let it sit for a 30 minutes. When I go to turn the key, they boat barely has enough power to open up one of my side exhaust ports, the other drags and stays closed because it's not getting the voltage to open it. I had to shut my exhaust off and wait til I started it to turn them back on. The boat fires right away, but with that being said... does it sound like my alternator might be on its way out? Could that be the reason my temp gauge is reading high because things aren't getting the required voltage with it running?

 

[Benny67]

Just curios here, did you use a pipe dope type sealer on the threads of the sender? If so, it will isolate the sender from the ground, and will give bad readings. They are put in with no sealer, so they make good contact to ground. Just something rolling in my mind....

Now there's a god question....

 

[Benny67]

Although he didn't change the sensor before he saw the problem

 

[trentbt1]

There is no thread sealer on the sending unit. It's safe to say the sender isn't the issue, i put a new one in a few days ago and it didn't help

 

[Benny67]

Did you ever just try a multi-meter in parallel with the gauge and monitor the voltage when it went to the bogus readings?

That was by far the simplest and easiest attempt to get some information on what's going on.

Might have kept a few bucks in your pocket too instead of throwing a sending unit into the equation that appears wasn't required.

 

[Benny67]

I took the boat out all weekend again and did notice a few things that popped into mind. When I take it down to the lake to start it up the first time, I flip on the ignition and the exhaust opens up with authority and alarm sounds. I do notice while the boat is not running but with switch on, the gauges do not move when I operate the trim, exhaust switch etc. when I start it and the boat is idling, that's when I notice the gauges going down when I operate switches/trim. It also acts like it wants to kill the boat at times. After running WO for awhile, I shut it down and let it sit for a 30 minutes. When I go to turn the key, they boat barely has enough power to open up one of my side exhaust ports, the other drags and stays closed because it's not getting the voltage to open it. I had to shut my exhaust off and wait til I started it to turn them back on. The boat fires right away, but with that being said... does it sound like my alternator might be on its way out? Could that be the reason my temp gauge is reading high because things aren't getting the required voltage with it running?

All of these issues arose AFTER the new battery install?

 

[trentbt1]

Yeah, it was normal for a few weeks and then that's when I started noticing weird stuff

 

[Benny67]

You had to have missed something when you installed the battery..retrace your steps....twice... It's too coincidental that these issues arose after changing the battery.

 

[trentbt1]

No offense Benny, but i'm getting tired of you critiquing me of things I have done wrong. I'm looking for someone that can try and help me solve the issue, not someone saying I have a cheap piece of **** volt meter, that i'm wasting money putting another sending unit in my boat and now, my dumbass may have done something wrong installing a battery. I get enough of that from my wife, I don't need your help. If you can assist with helping any further, by all means help out, but enough of the finger pointing. Anyways, I think i'm pulling my alternator and having it tested, it seems like the only issues i'm having is when the boat is running.

 

[bruceb58]

Anyways, I think i'm pulling my alternator and having it tested, it seems like the only issues i'm having is when the boat is running.

If you want to see if its the alternator, you can disable it by pulling off the field wire. Do not pull off the output without removing the field wire. If you find that's the issue, reconnect the alternator and measure the voltage with your multimeter on AC and see if there is much AC ripple being output by the alternator.

Hard to imagine it would be the alternator, but at this point, hard to imagine anything you have done to cause this issue either.

EDIT: just re-read your post number 29. The engine dying while you trim is a voltage drop issue. I had the exact same issue and it was a bad connection at the starter with the battery cable. I took them off and cleaned them shiny clean and reinstalled and that fixed the issue. If your alternator is failing, it could cause the same issue of low voltage. I know I got blasted by Benny for measuring the voltage drop but that would be my next step.

BTW...Electrical Engineer for over 30 years.

 

[Benny67]

No offense Benny, but i'm getting tired of you critiquing me of things I have done wrong. I'm looking for someone that can try and help me solve the issue, not someone saying I have a cheap piece of **** volt meter, that i'm wasting money putting another sending unit in my boat and now, my dumbass may have done something wrong installing a battery. I get enough of that from my wife, I don't need your help. If you can assist with helping any further, by all means help out, but enough of the finger pointing. Anyways, I think i'm pulling my alternator and having it tested, it seems like the only issues i'm having is when the boat is running.

good luck to you....spend the money on stuff you don't need...I should have just kept it to myself. Live and learn.

 

[Grub54891]

good luck to you....spend the money on stuff you don't need...I should have just kept it to myself. Live and learn.

:yield: