47-55.1 Battery charging issues

[pvienneau]

Hello all, took the 49 6 volt out this past weekend because had some work to be done. I was able to start up with a little either and choke. Once started I moved her out of the garage. After all warmed up I shut the engine off. When I went to restart the engine it wouldn't start. Starter turning slightly then dead. The battery is brand new and I even had it tested. So I put the charger/starter on the battery and it started right up. I took it for a ride and when I stopped the truck I shut it off. Went to restart it and again like the battery was dead. So I hooked jumper cables from a 12 volt car and it started right up. What are my next steps? How do I test the generator and voltage regulator? Thanks

[mr48chev]

You did step one= have the battery tested.
If the truck was sitting and not started and you started it by either hooking a charger or jumper cables to it you first have to check and see if the battery is actually fully charged or drained when you go to start it when it is cold.

First I would clean all of the battery cable connections and have clean bare shiny metal under every connection. That means SCRAPE the spots where the ground cables contact the block or frame to CLEAN BARE SHINY METAL. I've gone out and checked three or four just got it together and now it doesn't want to crank good vehicles and every time the issue was because the paint was insulating the ground strap from the block. I actually had one guy cry and fuss when I pulled out my knife and scraped the paint off from under the ground cable and put the cable back on. The car started right up though.

Then get out your multimeter and fire the truck up and check the voltage at the battery, Remember generators don't charge much at an idle and you need to speed the engine up a bit to see if it is charging.

Click on section 12 http://chevy.oldcarmanualproject.com...ruck/index.htm Then you can either read page by page though how the charging system works or go to page 12-8 where the trouble shooting and testing part starts and continues for several pages. I'd read start to finish just to learn how the system works. They wrote the old manuals in very basic language and the good thing is that they didn't assume that the mechanic working on the trucks had any experience. It is almost as basic as the how to repair your VW for idiots book that came out in the 70's.

The contact points in the regulator can arc and stick just like ignition points. You can clean the contacts up with a point file or snag a small emery board and use it.

If the generator hasn't been freshly rebuilt the brushes may be worn down and need replacement. They aren't hard to freshen up but can be a bit of a challenge the first time or two a guy does one. The fun being figuring out how to get the brushes to slip back over the commutator of the armature.

[_Ogre]

if you fully charge the battery and you say it starts right up,
it should be able to start and run for a few times and miles without needing charged again
i suspect a draw on the battery

it's been a while since i worked on a generator
i'd start by polarizing the generator again
you should know how to polarize a generator since you own one
if not http://starautoelectric.com/instruct...ing-generator/

if that doesn't work, time to pull it apart and check the brushes, easy peasy
then you move on to the regulator, but check those first
doesn't hurt to check out and maybe continuity check a few wires

[pvienneau]

Thanks, reading the manual and going through the steps. I'm confident I will find the root cause and fix it. Just sucks when you need the truck and it ****s the bed. What are your opinions on battery tenders?

[1project2many]

What are your opinions on battery tenders?

Do you have anything electronic in that truck? Clock? New radio? Are you using a solid state voltage regulator or a mechanical points type? If there's nothing drawing power the battery should remain charged for a *long* time. My Plymouth sits through the entire winter without a charge and the four year old battery will usually crank the engine enough for it to fire off with starting fluid! Some simple checks include visually looking at the top of the battery for water/acid which can discharge the battery across the terminals, and watching for sparks when reconnecting the battery cables. If you have sparks, confirm nothing is switched on then suspect stuck points in the regulator as previously mentioned. If the points are stuck the generator may be trying to turn the engine and will get warm to the touch.

One other thing to note is that charging voltage is important with old or reproduction lead-acid batteries. Generator systems with mechanical regulators tended to need tweaking to match the type of driving the vehicle sees most. If you do more highway driving you would set the regulator for voltage on the lower end of the scale to prevent the electrolyte from getting too warm and evaporating out of the battery where it will condense on the top of the battery. If you find the battery is wet then suspect the charge voltage is climbing too high. Clean the battery then begin testing.

Keep the manual handy!

Also, if you'd like to make some modifications to your system which can be hidden from sight, there are a number of solutions to put a solid state regulator into the system. It might be worth it to convert...

[MiraclePieCo]

Haha, my procedure is parts replacement, in order of either 1) most likely item to fail, or 2) cheapest item. Inefficient and expensive? Maybe, but it's saved me a ton of time testing and troubleshooting!

[1project2many]

Inefficient and expensive? Maybe, but it's saved me a ton of time testing and troubleshooting!

It's a common strategy I see. It's probably second to "diagnosis by consensus" where you ask a bunch of people or a large group to solve the problem then work from most common answer to least common.

[JoeDude]

Anyone know where to get a solid state 6v voltage regulator that looks OE for a 54 3100?

[_Ogre]

Originally Posted by pvienneau

What are your opinions on battery tenders?

58truk has the alarm system, mostly for the remote entry, lack of door handles
it will kill the battery in a week if i don't drive it or plug it in
i swear by the harbor fright trickle charger and plug truk in all salt season
every spring truk is charged and ready to go with the turn of the key
this is my 2nd one in 12 years, i think a bad battery caused the last one to burn out at 5 years

right now it's $10 and well worth that, but hf puts it on sale for $5 often

harborfreight.com/automatic-battery-float-charger




i bought an official battery tender many years ago on sale $30 for when this hf unit burns out

[1project2many]

Anyone know where to get a solid state 6v voltage regulator that looks OE for a 54 3100?

I've never used these folks but they do show what you're asking about.

https://www.qualitypowerauto.com/ite...Regulators.htm

[pvienneau]

The truck is all original. No radio. Original wipers work fine not electric.

[mr48chev]

You do have a multi meter or volt meter?
With a meter set on DC volts connected to the battery you should show about 7.1 volts with the engine speeded up a bit. Generators normally do not charge very much at an idle and some don't charge at all until you get the rpm up.

As far as that goes, if the needle on the ammeter shows charge when you are going down the road that should be good and move on to the next thing.

Next thing: Like going to the Indian health medical clinic that I go to quite often when trouble shooting the first issue you think of is what you look for all day long and you miss the reall issue.
Simply:

Does it show a charge on the ammeter or the multimter you connect to the battery when you rev the engine up a a bit Yes--- NO _______

Have you had the battery tested. I don't give a rip if you bought it this morning if you have issues has the battery been tested?

What is the condition of the starter? The starter may be dragging or have worn brushes. Brushes, bushings and or bearings for the starter don't cost much and aren't that hard to change.

What size are the battery cables? Those skinny cables sold at Autozne or O'Reilly's or other parts houses won't carry the amps that 6 volts is able to push very easy. When I was teaching autoshop I used to use an old Mopar training film to teach Volts, amps and Ohms. This was from the early 50's but it explained it in very basic down to earth terms. Think water pump and water pipe.hose. You can push a pretty good volume of water though a 3/4 inch pipe and hose with a small pump but the same small pump won't move near as much water though 1/2 inch pipe and hose. The pressure at the pump will be good but the flow is restricted. That is why you need larger cables with 6 volts than 12 volts. you don't have the pressure to push the amps though skinny cable.

Test and check before spending money. when it cranks slow get out and start feeling cables and see if one is hot to the touch. That means extra resistance an you need to trace the resistance down.

Last, don't be afraid to ask questions. That includes sending me or one of the others you feel has the right answer a pm if you feel the need.,

[JoeDude]

So the positive cable should never feel warm?

[_Ogre]

Originally Posted by JoeDude

So the positive cable should never feel warm?

no. maybe a little after a long crank, but warm is usually a sign of bad connection or under sized cable
if you have an issue, you should start a new thread

[mr48chev]

The positive cable can feel real hot and even burn up if the resistance issue is on that side going to the starter or what ever else you are having an issue with.

in 58 years of working on cars and trucks I have far more bad connection issues on the ground side than the hot side. Guys usually pay very close attention to connecting the hot side from cable end to the starter. They often ten to be lax on the ground side.

If the "hot" cable is hot that usually means that what ever you have an issue with be it starter or light or what not is defective in one way or another. I say HOT side simply because we do have rigs with a positive ground electrical system including 6 volt GMC Trucks.

Still it is never assume, in that you always need to inspect and test rather than assume.

This is a case of that. Just because the truck fires up at home and then doesn't want to crank 30 minutes and three miles later doesn't mean it isn't charging, The starter could have bad bushings and be dragging. The battery may be marginal and won't crank the now heated up with engine heat starter. There may be a resistance in a connection.

I fought my 77 for a long time and even replaced the starter when it wouldn't crank when hot and finally changed battery cables to larger diameter cables to fix it. The skinny cables wouldn't carry enough amps to crank it over good.

[pvienneau]

UPDATE, I was able to get to working on the 49. Detached all battery cable connections, straps and cleaned all surfaces with wire brush and sand paper. Charged the battery and the truck started up. I shut it down as I did before then it started right up hot. I di this several more times waiting longer between periods of rest. Next is the over night test.

During my research the number on recommendation was to clean everything and it seemed to work, however I also read lots of recommendations to update the battery cables to 00 Gauge. Is this something you guys think I should do? Right now the hot to the starter is 2 Gauge. Thanks for help everybody.

[pvienneau]

Never mind, I went out and tried starting her and no go. It's like a dead battery now.

[pvienneau]

Now I disconnected the battery terminals from truck and recharged the battery to 100%. I will reconnect the battery to the truck tomorrow to see if it's dead. If so I will return the battery for a new one. If the battery holds the charge then it must be something drawing it down on the truck. However the only draw would be from the key switch. It has nothing else drawing on battery that I know of.

[mr48chev]

Is the top of the battery clean and dry? A dirty battery top with a bit of moisture can cause a parasitic drain across the top of the battery. You can check that with a volt meter by hooking the meter to one post and using the other lead to touch around on the battery top to see if you get a reading.

Do you have a return spring on the brake pedal that pulls it up tight against the foot board and holds the stop light switch in the off position? If not the pedal may be dropping down and turning the brake lights on without your knowing it. That can happen pretty easily if the brakes aren't adjusted up good.

You for sure need to change to the larger cables or at least the correct diameter cables.

Did you actually check to see if the generator is charging the battery?

Most rigs with a good battery can be drive a few miles and started several times without draining the battery down so they won't start. I've been around plenty of dirt track cars that didn't have any generator or alternator on them at all. Just a battery that they charged before they went to the races on Friday night and they raced all night with it.

[dsraven]

check and clean all connections, like you did already. ensure you lay hands on ALL connections, positive and negative. everywhere. battery, starter, fuse block, grounds, ign switch, starter and the "stepon" starter switch, dah dee dah.
do a voltage check before and after start up. after start up should be more than before start up. you gotta rev it up to get the generator working while you do this because the generator doesn't charge a lot at idle. if you generally start it and let it idle for extended periods to "keep things lubed up" then the battery may not be getting charged well and that can be a problem right there.
if your battery was dead for a bit or low on acid it may have sulfated the plates which means there is a coating on the plates so the chemical reaction can't happen on that area. charge the battery with a fast charge to help break that sulfate off if that is the case. the adverae affect here is that stuff that breaks off the plates becomes sludge below the plates, which can move around while driving and end up shorting out the plates in that cell. have the battery load tested. ensure it is fully charged and then allowed to sit and rest for a bit and then apply a load of 1/2 the cold cranking amps for 15 seconds -the voltage would not drop past 5 volts. use a carbon pile tester if you have one available or check around at starter alternator generator shops to see who may know something other than what google says on their phone. most auto supply shops have a digital unit that is calibrated for 12 volt batteries so the school kid behind the counter will likely say your battery is toast no matter what.
next check the starter draw. you will need a few electrical tools to do this like an amp meter and how to hook it up. an amp meter with a pick up probe clamp that wraps around the battery cable to the starter would be good, then you will get actual starter draw. disconnect the coil wire high tension lead and ground it so the engine won't start. this probe clamp can also be used to check the amperage the battery is receiving when the engine is running by clamping the probe around the battery positive cable. if you have one of those carbon pile testers you can start the engine and apply a load using the carbon pile to see what the generator is putting out through the amp probe. google sun AVR meter for the old fashioned unit. usually the AVR will say what the amp load is as you crank down the carbon pile and when you see the voltage drop that will be the generator output at that rpm.
check the battery cable to the starter, do a voltage drop test to ensure the cable isn't becoming a big resistor. if the cable is getting warm then there is resistance somewhere near the warm spot or else the cable is undersized or the starter draw is more than the cable was rated for. if you have one or several of those braided ground cables you may also want to check that for a voltage drop. whatever voltage or amperage passes through the pos cable also has to pass through the neg cable or ground system. check the shielded/insulated cables for lumps along their length as those lumps are likely corrosion inside the cable which is a resistance. a damaged cable can have corrosion around a break in the insulation wrapping. crimped on termi9nals also are a great spot for corrosion inside the crimp or down the cable shielding if there is no seal on the insulation at the end of the cable.
if you boost with 12v on a 6v system you may cause damage to other things in the system that don't really like to be over voltaged.
unless you are tied to a 6v system you could upgrade to a 12v system and use the original 6v starter as long as the engine tune up is good so the starter doesn't have to be cranked for longer periods. the old 6v starters will handle 12v really well. google the swap procedure for what it takes if you are interested. 12v alternator will charge well at idle and the 12v will spin the 6v starter slightly faster than 6v did so the engine may even fire up quicker. just a thought. battery, alternator and electrical plug, all bulbs, horns, and a guage resistor set up would be required. 12v radio as well if you have one or at least a voltage drop system of some sort.

[pvienneau]

I just went out and attached the battery and she started after after a couple tries, but the battery seemed strong and did not go dead over night.

[dsraven]

When you connected the battery was there a little spark when you touched the cable to the post? If so you have a draw on the system somewhere.
Just wanna say, also, be carefull doing battery connections after charging a battery. There are flammable gasses given off when charging which collect in the air space above the acid and eventually self vent. a spark generated from connecting a cables could cause those contained gases to blow the lid off the battery right in your face. Some will say that is few and far between, like I used to say until it happened to me. I was lucky to have a friend with me and I was close to a garden hose.

[mr48chev]

OK now when you put the volt meter on it and check it while running how many volts does it show?

[pvienneau]

OK, I will not leave charger in cab anymore. I get no spark and I tested with key in on pos and it did the spark thing. When I just went out and connected the battery it wanted to start but it's not turning over like I'm use to. It wants to start but won't. Once I get it running I will check with Volt meter.

[pvienneau]

OK, I think I found the short in the Cab light. I removed the light completely from the truck and been test starting without same issue. SO I'll give it one more day before I take it out for errands.