Locating Parasitic Battery Drain

[iicap 1]

Sorry for the delay getting back, but now let tell you what I found.

After removing the ammeter from the tractor, I again did a continuity test holding the ammeter in my hands. I still had continuity from case to studs. I have pics of the ammeter I'm going to post here.

Now, I DID NOT do what SOI had suggested, I didn't heat the ammeter with a hair dryer, reason being this tractor has been in my garage (attached to the house) for about 5 weeks, a well insulated, dry environment.

I did open the meter as suggested, but looked it over very well and took pics before doing this. As you'll see in the pics there is/was a corrosion (galvanic?) that appeared to bridge from the retainig nuts across the insulators to the case. I took the ammeter and scrubbed the stud/nut/insulator/case area with an old toothbrush and some baking soda toothpaste. I did the test again and still had continuity.

Ok guess it's time to open the ammeter. I removed the bezel and lens then the stud nuts. slid all out of the case and it was absolutely perfect inside, no signs of any corrosion, no arcing, dry, no moisture stains. The only abnormal thing was the needle at, rest was always to the charge side a bit and the chassis the needle rides in was twisted downward on the charge side, you may see it in the front view pic.

So with nothing obvious I assembled the meter again, minus lense and bezel. I cleaned the nuts and scraped the corrosion from the case and insulators and turned the insulators over so the smooth side was up/out against the nuts and tightened all. I did continuity test again, NO CONTINUITY, put the lense and bezel on just crimping it in 4 places to hold together as definately would be throwing the gauge out. Still no continuity. Installed it in the tractor, no cont. All wires hooked up tested for voltage draw, 00.00, no drain.

Conclusion, parasitic draw caused by galvanic corrosion, bridged from the stud nuts across insulator(s) to ammeter case. If I had cleaned with a wire brush and scraped the visual corrosion I probably would have broken the bridging and salvaged the meter but I didn't know what I was looking for. The pics follow, thanks for reading

meter front, you can see slightly to charge side and pivot point chassis tipping down right

This is prob the best pic of corosion look across the black insulators nuts to case, nut left 5to7 o'clock position, nut right 4to6 o'clock position.

This pic again showing corrosion at 2to4 o'clock

Just another pic, no depth or clarity as in the others

[WheelHorse_of_course 99]

Thanks for sharing this.

[horsefeathers 15]

Well Chuck... Looks like we've opned up a can of "Galvanic Corrosion"!

I found the amp meter I installed on the "Gasser" was the culpret also.

I disconected the amp meter bolted the wires together and O draw.

I didn't question why... just a junk meter. Now I know more!

Loose wires, rust, corrosion, I should have known better!

Rust to ground come in ground...come in ground... copy ya rust!

HORSEFEATHERS!

[Save Old Iron 1,566]

Wow.

makes you wonder if those fiber washers insulating the wiring posts from the meter case are the culprits.

It is possible the material those insulators are made from may absorb moisture and conductive "stuff" over the years and end up being a resistor instead of an insulator.

Interesting. The 3 meters I looked at all had plastic cases and plastic gauge support brackets.

Thanks for the feedback. By the way Bud, when you measured the parasitic drain, did you happen to note how many milliamps of current was flowing as parasitic current?

[iicap 1]

Thanks to horsefeathers and SOI on the last two posts.

I would ask another ?, BUD have you tried removing the nuts and insulators from the case and cleaning all to see if the meter could still be used? I would do one stud at a time. I bought a new ammeter (made in Ch---), impatiently, wish I still had the original that was made right here in CT.

Richard

[TT-(Moderator) 1,145]

The 45-0-45 ammeter that Richard has pictured above isn't a good choice for use on the 15 AMP systems normally found on tractors. I doubt you'd even be able to see the needle move.

A 20-0-20 will actually allow the operator to see some needle movement. :banghead:

[iicap 1]

TT, this tractor is an AC 314D. All electrical load, except the starter motor, goes thru the ammeter, thru the ignition switch(yes) to a distribution block with one stud, 4 off lead wires stacked on the stud. Tractor has a linear actuator for rear attachment lift, electric front PTO, sealbeam headlights, one tail, cigar lighter. I was going to use 20-0-20 from my C161 but decided against it. All these accessories, because they go thru the meter and the 45-0-45(I'm sure was OEM) was distorted at the needle pivot chassis, possibly from getting hot. I ended up getting a 60 amp gauge, only one available, me being impatient.

Wondered if horses fed their electric actuators and clutches from a source that didn't go thru the ammeter and alowed using 20-0-20 meters?

[iicap 1]

SOI and all, when I stated in my diagnostic post that "the DVOM read 00.06 which I believe is 6 hundredths of a volt", I believe I should have said 6 hundredths of an amp. Is that so?

[TT-(Moderator) 1,145]

Wondered if horses fed their electric actuators and clutches from a source that didn't go thru the ammeter and alowed using 20-0-20 meters?

The old accessory electric lift kits were fed using a relay (basically just starter solenoid) triggered by the "L" or "A" terminal on the ignition switch. Power for the actuator motor never passed through the ammeter.

The load of the lights, electric clutch, cigarette lighter, hour meter, and ignition coil power (if applicable) did pass through the ammeter though.

Looks like the A/C 314D used the typical 15 amp stator too, but now I see why the 45-0-45 meter was needed.

[Sparky-(Admin) 21,403]

I dont have a tractor with a battery drain issue (yet ) but this is a very interesting thread guys. I'll have to remember all this when its my turn with a dead battery.

Mike..........

[Fiscalyear 0]

IICAP - Richard.

This post you started could have been written by me about a month ago, word for word. WOW It was as if you were writing the procedure I used to find a drain on my Ammeter. Same problem. Identical, and yours were with pictures. Great.

I realize most people don't jump under the skin of defective electrical components but I do because that was my MOS (Military Occupation Speciality) many years ago. Electronic Instrument Device Repairman - short for what other electronic training students refered to as "Meter Beaters". I guess we were meter beaters but we also had to repair most all small device electrical equipment. AHH - the good old days. Forgive me for drifting. Back on the ammeter.

I'm sure this situation exists with a lot of our Horses' ammeters but to a lesser degree of battery drainage and possibly don't show up because we either run our Horses every few days or some of the (parasitic) Horses do not have batteries installed all the time. Can you imagine how many batteries some of you guys would have to own if you kept a battery in every Horse you own?

Here is where I swaped out the silly ammeter by just wireing it straight through and installed a 0-15 DC voltmeter in it's place. No more current draining ammeter but a more useful voltmeter. A voltage reading can be more desireable than a pointer in most ammeters, especially OLD ammeters.

Great site guys - I love it here. Eddie

[iicap 1]

Fiscalyear, thanks for your response. I agree with you on the installation of the Voltmeter. I prob should have put one on the AC 315D. This tractor doesn't need to be politcaly correct in appearence, but I know many tractor owners want there's to be and I like that. In another thread active recently about jumping ammeter needles, the voltmeter would be a great update. It's all our personal choice.

[sprintcat 0]

I just bought a 1963 953 and when i take off the negative cable you can almost weld with it when you put it back on . this tractor is new to me so not sure whats going on with it yet, and the battery is always dead.when its connected it turns over and starts with no problem.

[rmaynard 15,588]

Here is a wiring diagram. Start disconnecting everything that attaches to the positive lug of the battery, one at a time, until the ground no longer sparks. Does it spark with the key off?

If you have a multimeter, go to the very beginning of this thread and read how to track down the culprit using a meter. The wiring on a 953 is very simple. You should be able to locate the cause very easily.

[sprintcat 0]

yes Bob it does spark with the key off . i will try what you said and let you know . Thanks

[rmaynard 15,588]

With the key turned to on, all you are doing is providing a path for 12 volts to go to the coil and to the generator light. If the key is off, the generator light should also be off, and you should not have any voltage at the (+) side of the coil.

You say that it happens with the key off, so with the key off, you have 12 volts at the center tap of the regulator, and at one side of the starter button.

I would begin by removing the wire from the center tap of the regulator. Chances are pretty good that the regulator is bad.

[sprintcat 0]

Turned out to be the starter button. I will have to replace it . part # 892303 . wow that thing ain't cheap

[WH nut 553]

Now that's an excellent tutorial.

Bob

Good job as always