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Old 07-05-2023, 01:01 AM   #76
dsraven
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Re: Battery draining

0.07 volts is a pretty small draw. can you get an amp reading on that as well? seems like a 7/100 of a volt draw could be a meter calibration even. check for an amp draw and you will see how much current is being used that amounts to that voltage draw, if any. to get 7/100 volt draw the draw would need to be through a bunch of resistance, thats not even enough to light a bulb. as an example, one of those little 194 bulbs would draw less than 3 amps at normal battery voltage.
a simple way to figure it out is ohms law. basically voltage equals amps x resistance. you could google ohms law for a tutorial on it, how to use it for valtage drops in circuits etc.. basically you disconnect the battery and then connect the multimeter (set to high dc amps) in series. connect the one lead to the cable and the other lead to the battery. all current will go through the multimeter so makw sure you do this with the key off. normally this is when I would start pulling fuses untill I find the one that makes the current draw go to zero when the fuse is pulled.
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Old 07-05-2023, 01:21 AM   #77
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Re: Battery draining

in your case you would leave key turned off. connect the meter in series like above, then, if you get an amp draw, disconnect one thing at a time until the draw goes away and the meter says zero. the last thing you disconnected to get the zero is the culprit. if you disconnect something and the meter reading changes but doesnt get to zero with that change then that simply means whatever that thing is that was diasconnected last and made a small change is also a parasitic draw so you have more than one thing using battery with the key off. since you dont have much connected, really, this should be a quick test and wont cost you anything but time. dont frorget to check your starter solenoid for dirty connections that may be leaking current across, say, grease used to prevent corrosion. some grease conducts. same scenario as mr48 was talking about with the dirty battery top.
anyway, good luck and hope you find the problem and post a pic.
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Old 07-05-2023, 01:26 AM   #78
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Re: Battery draining

i just looked back to your pic of the alt and noticed how nice and clean and painted your stuff is. very nice. I wonder, though, if the paint is making it hard for you alt to find a proper complete ground. maybe try running a jumper wire from a good ground over to your alternator housing.
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Old 07-05-2023, 02:21 PM   #79
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Re: Battery draining

Quote:
Originally Posted by dsraven View Post
i just looked back to your pic of the alt and noticed how nice and clean and painted your stuff is. very nice. I wonder, though, if the paint is making it hard for you alt to find a proper complete ground. maybe try running a jumper wire from a good ground over to your alternator housing.
That will not have anything to do with his problem. If it wasn't charging right when it was running THEN it would be the problem. I lost track of the number of vehicles that I have gone and looked at that either hada won't start or won't charge issure where that pretty paint that the owner didn't want to scrape off to bare metal was the problem as it didn't allow the connection to ground.

The problem is that the battery is draining when the truck sits for a length of time but not a long length of time. A bigger problem may be assuming that something is good just because it is fairly new and not testing it.

Now we go down the list
Has the battery been properly tested with a decent test machine" Yes/no.

If he removed the battery and hauled it home, fully charged and let it sit at home for several days does it maintain charge?

Has the alternator been removed and taken to a shop or store that can properly test it with their test machine? Yes/no

Have the fuses been pulled on accessories that may cause a drain when the truck is sitting in the garage not running?

It's not hard in most cases to unplug the brake light switch to see if the pedal drops over time. That could be an issue if no one else walks in where it is stored during the time it would take to drain the battery.

Assuming that something is good because it is new is one issue that folks do too often.

Following behind somone else and especially someone else who wired a car or truck can be an issue because you are constantly trying to figure out what they did and why.

As i said before to me the rub with Painless wiring kits and especially the truck kits is that they are UNIVERSAL and one kit fits several brands with add on sub kits doing some of the jobs. Scrolling down though the directions for the Truck kit you have Ford directions, Chevy directions, Dodge directions and maybe if directions. If someone isn't paying attention they could hook somethign up wring. Then we throw those in who don't follow directions who make a bigger mess. I'm not saying the kit is the problem but I sure would not reccomend one to anyone who is working at a beginner level.
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Old 07-05-2023, 02:53 PM   #80
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Re: Battery draining

I've seen poor grounds cause some weird stuff, that's why I mentioned it.
Good point mr48, remove ALL the fuses that are not needed to run the bare essentials that are connected. Just to be sure a circuit isn't touching somewhere it shouldn't when it's not connected to the intended use yet.
Phungki, you can spin that ohms law equation around to find whatever part of it you dont know yet. It's not gonna help you find the draw but will let you know what the amps and resistance is so you can look at what in the circuits you have connected could possibly draw that much. Like is there a powered 4 way flasher connected through the fuse box, etc.
I would still check the circuitry at the alt, white wire especially, to see if its powered with the key off.
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Old 07-05-2023, 08:58 PM   #81
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Re: Battery draining

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Originally Posted by leegreen View Post
Which terminal on alternator does that siamesed wire go to?
the two wires in the plug? white wire shares a terminal with the brown ACC wire that goes to the ignition switch. Red wire goes to the terminal with constant power
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Old 07-05-2023, 09:05 PM   #82
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Re: Battery draining

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Originally Posted by dsraven View Post
i just looked back to your pic of the alt and noticed how nice and clean and painted your stuff is. very nice. I wonder, though, if the paint is making it hard for you alt to find a proper complete ground. maybe try running a jumper wire from a good ground over to your alternator housing.

I can do that but I do use the alternator housing as a ground when using the test light. Its got enough ground for that.
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Old 07-05-2023, 09:46 PM   #83
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Re: Battery draining

I tested the battery its 12.67v. Its been holding here pretty steady. 7-10 days without being hooked up much other than to test.

with the ignition, starter and alternator hooked up but the key is off, its neg 12.65v

white exciter wire does not have power. neither does either of the terminals on the alt.

I completely disconnect the ignition, still reads neg 12.65v

remove the plug from the alt it reads neg .88 slowly ticking down

I get a good ground test on the alternator using the MM checking continuity.
The terminal on the alt that the exciter wire connects to also tests for ground. should it?

I took a couple picks to show my readings. I think I have the meter dialed in right. someone will tell me if its not I hope.

Mr48 questions

battery tests 12.6 with MM. bets way I have to test it. it does hold a charge unhooked for days.
Alternator has been tested at o'reillys

I've only pulled fuses to see it they are causing a draw. No accessories in the truck to draw

brake switch isnt hooked up either same goes for brake lights

I get the new doesnt mean good aspect. ran into that with my jeep before.

I read alot of threads on this forum about wiring and I read good reviews on this painless set.
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Old 07-06-2023, 02:57 AM   #84
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Re: Battery draining

what do you have connected, electrically, on your truck
-battery-obviously
-starter-obviously, but how many wires are on the starter solenoid, one big battery cable and a single wire to make the starter operate? a third wire possibly? a pic would help
-distributor-obviously but what distributot are you running and what wires are connected to it and how? a pic would help. seperate ign coil or integrated into distributor cap?
-ignition switch- obviously but which style and how is it connected? column mount, dash mount etc
-fuse panel-yes. all fuses are pulled except ones needed to run the engine circuits?
-fuel pump-no since it is mechanical by the pics
-cooling fan-no since it is mechanical by the pics
-tachometer-?
-gauges-? do you have any gauges connected to monitor engine basics and if so what are they and how are they connected electrically?
-lights-?
-any accy-? radio, cig lighter, alarm, etc.
-wiring in steering column or turn signal switch etc?
-anything else connected electrically? all un-used wires in harness are capped? is harness simply coiled up or is there loom for some circuits that have been strung out and connected to the basics things it takes to run the engine?

can you lay out a drawing of what you have connected and how? pics always help. a pic of the connection side of the ignition switch, distributor, starter, fuse panel etc. it doesnt take a lot for simple engine start/run so we should be able to put our heads together and figure it out. connecting an amp meter in series isa start to find out what the draw could be. possibly a gauge getting fed power with the key off or something similar
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Old 07-06-2023, 10:52 AM   #85
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Re: Battery draining

Flip that knob on your meter all the way around to the 10 above the A
Turning it into a amp meter.
With truck ignition OFF disconnect the negative cable from battery.
Touch one lead to the negative battery post and other to clean ground metal on truck and get us a pic of the reading.
this puts the meter in series and will show you the amp draw with nothing turned on.
don't use the smaller setting it will pop the fuse in the meter. start with 10 and work down etc.
DON'T do this to test starter draw when cranking. it is not designed for that type of test. But works fine for all most other checks since they are usually way under 10 amp draws.

you should have a very small number with nothing hooked up it should almost not read anything but lets see.
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Old 07-06-2023, 11:01 AM   #86
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Re: Battery draining

thats the test I was suggesting as well, key off amp draw.
phungki, if you could show in your pics where both ends of your meter are connected it would be best for clarity.
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Old 07-08-2023, 03:01 PM   #87
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Cool Re: Battery draining

Quote:
Originally Posted by Hcb3200 View Post
Flip that knob on your meter all the way around to the 10 above the A
Turning it into a amp meter.
With truck ignition OFF disconnect the negative cable from battery.
Touch one lead to the negative battery post and other to clean ground metal on truck and get us a pic of the reading.
this puts the meter in series and will show you the amp draw with nothing turned on.
don't use the smaller setting it will pop the fuse in the meter. start with 10 and work down etc.
DON'T do this to test starter draw when cranking. it is not designed for that type of test. But works fine for all most other checks since they are usually way under 10 amp draws.

you should have a very small number with nothing hooked up it should almost not read anything but lets see.
I didn’t get any readings at all. Not sure what this means.
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Old 07-08-2023, 03:40 PM   #88
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Re: Battery draining

Ok that means you have don’t have a big amp
Draw. Move meter down on click lower than 10 and do it again.
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Old 07-08-2023, 03:42 PM   #89
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Re: Battery draining

Your positive truck cable was hooked up to
Battery
Correct ?
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Old 07-10-2023, 01:30 PM   #90
dsraven
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Re: Battery draining

one side of battery connected like normal, say the positive is connected. the negative battery cable is disconnected. place the amp meter between the negative side battery terminal and the negative side battery cable, with meter on max amps to start. then, depending on if there is a reading, go lower till the meter is in range.
a very low amp draw would mean there is a very small draw. a clock, stereo memory or something would be the go to but you don't have anything connected other than the basics. is there a gauge package connected at all? possibly not on the "hot in run only" circuit?
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Old 07-10-2023, 08:52 PM   #91
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Re: Battery draining

Quote:
Originally Posted by Hcb3200 View Post
Your positive truck cable was hooked up to
Battery
Correct ?
Yes positive cable is hooked up. Now Im sure I’m going to show my ignorance here but…..what is lower than 10 here?
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Old 07-10-2023, 09:02 PM   #92
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Re: Battery draining

sorry, most MM's have a 10 amp dial position as a max and then they also have dial positions for lesser amp stuff, mili-amps. start on the 10 amp setting and see what it says, if it says decimal zero zero something then go to a lesser setting on the dial until you get a reading that is closer to the decimal point.
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Old 07-10-2023, 09:34 PM   #93
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Re: Battery draining

I’m even more confused now then when I started 🤔.
After going thru the things that were suggested when I could. (Bad timing for me right now). I added a ground from the body to the frame. I changed the wiring on the alternator to (pic attached). I switched the alternator. I messed with the ignition, checking and rechecking the wiring. Plugging and unplugging fuses. Added a diode on the exciter wire going to the alternator. Every time I did anything I rechecked for draw. Always the same (-12.66) unless I unhooked the small red wire going to the alternators plug which gives me a -0.88. After determining that everything just looked right, I decided to leave it hooked up. Even started it tor a few. I left everything hooked up. Surprisingly in was fully charged still after 36 hrs. Got a 12.6v reading on it. But it still shows a neg 12.6v draw. How is that possible? Operator error probably lol. Does it look like I have it set right? Unfortunately I don’t know what thing I changed that stopped the battery from going completely dead in 24 hrs. Since I’m still getting a neg reading.
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Old 07-10-2023, 09:52 PM   #94
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Re: Battery draining

Well you did do like 6 things without testing between each one my guess is going to be the diode between the alternator and battery. Or a wiring that’s now hooked up correctly.
And that 12 volts you’re getting IS NOT DRAW that’s voltage. It should always say 12 unless you are actively starting with starter.
AMPs is draw and the only way to test it is put it on A and in line with the negative post and ground. It should zero if you don’t have any electronics Hooked up with switch off. ( add radios and computers and you get a super small draw ). If you want to see what your system is drawing without starting then key on meter on A 10 and put it between post and ground and you should see a small number less than 10 but greater than 1.
But most important glad it’s working. Time to move on what’s the next project on your ride.
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Old 07-10-2023, 10:13 PM   #95
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Re: Battery draining

Well you did do like 6 things without testing between each one my guess is going to be the diode between the alternator and battery. Or a wiring that’s now hooked up correctly.
And that 12 volts you’re getting IS NOT DRAW that’s voltage. It should always say 12 unless you are actively starting with starter.
AMPs is draw and the only way to test it is put it on A and in line with the negative post and ground. It should zero if you don’t have any electronics Hooked up with switch off. ( add radios and computers and you get a super small draw ). If you want to see what your system is drawing without starting then key on meter on A 10 and put it between post and ground and you should see a small number less than 10 but greater than 1.
But most important glad it’s working. Time to move on what’s the next project on your ride.
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Old 07-11-2023, 08:52 PM   #96
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Re: Battery draining

Quote:
Originally Posted by Hcb3200 View Post
Well you did do like 6 things without testing between each one my guess is going to be the diode between the alternator and battery. Or a wiring that’s now hooked up correctly.
And that 12 volts you’re getting IS NOT DRAW that’s voltage. It should always say 12 unless you are actively starting with starter.
AMPs is draw and the only way to test it is put it on A and in line with the negative post and ground. It should zero if you don’t have any electronics Hooked up with switch off. ( add radios and computers and you get a super small draw ). If you want to see what your system is drawing without starting then key on meter on A 10 and put it between post and ground and you should see a small number less than 10 but greater than 1.
But most important glad it’s working. Time to move on what’s the next project on your ride.
My pics in post #93 shows a neg 12v in one picture and just 12v in the other. Just trying to understand that.

I did post that I rechecked after each thing I changed.
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Old 07-11-2023, 09:29 PM   #97
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Re: Battery draining

Because that test on 93 looks like it’s in series that’s showing a backward flow so to speak. Since alternator was not running. Had you just flipped the leads around it would read positive. If you tested voltage in parallel with leads o. Correct positive and negative it will always read positive. But in series It reads how it thinks the amps are flowing for lack of a better term. Been a long while for electronics class.
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Old 07-11-2023, 09:32 PM   #98
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Re: Battery draining

understanding the negative and positive showing on the digital screen, from seemingly the same connection, is understanding how the probes were connected. it is the nice thing about a digital meter, it will show a negative reading rather than pin the needle at zero on the analog style meter if it is connected backwards. (unless you have an analog meter that shows as much negaite scale as it does positive). so if you get a negative reading and simply swap the probes around it will then show a positive reading. dunno if that makes sense
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Old 07-11-2023, 09:34 PM   #99
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Re: Battery draining

either way it shows the amperage flow and the available voltage between the probes of the meter
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Old 07-12-2023, 01:08 AM   #100
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Re: Battery draining

It sounds like you already fixed the large battery goes dead overnight problem.

When the MM gets confusing, you could put your new test light between battery and negative then disconnect stuff one change at a time until the light goes out.
Leave that last thing disconnected, it is one of the problems, maybe the only problem.
Next double check to see if there is a second problem: reconnect everything else to see if one of them makes the light come back on
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