The Stovebolt Site Forums The Shop Area The Electrical Bay HELP!

I'm having a battery/electrical issue. I bought a new 6 volt battery fully charged and it started right up and showed charging while it was running. Now if I test the battery with the key off, I get 5.2 volts and with the key on 2.5 volts. Where is the current going? It doesn't' have enough power to start the vehicle. Dead short??

First see if you have a short when the key is off.

Disconnect the ground wire from the battery and put a continuity tester between the battery and the ground wire. If it shows continuity, you then have to start disconnecting leads until the light goes out - that would be the connection/lead/device that is shorted and is draining the battery.

If this does not find a short, report back for further instructions/suggestions (which will be: do the above tests with the key on).

By the way, did you try starting the engine right after turning it off?
How much time elapsed before you measured the battery and tried to re-start?

the only thing I can tell you is with the key in the off position, the battery reads 5.8 volts. with the key in the on position, it reads 2.5 volts. I think this battery is toast.

Do you know how to check the cells in the battery ?

If you had that big of a short, you would be seing some heat from somewhere. A volt meter with some cheap ends, (you have to touch the acid in each cell with them, or make sure you clean with water) youcan measure the reading from cell to cell and you should get around 2 volts. If the combination between cells read low, in any combination would tell you that cell is dead. Or find a hydrometer, all cells have to rear the same, or battery is toast. If batteries OK, See if draw is on acc or ignition.

OK so I have some questions for you:
1 Why did you get a new battery?
2 Have you done any electrical work recently?
3 What is the shape of your electrical system? Is it new, old or a mix match of old and new?
4 Are you starting your truck for the first time and the new battery was for this reason?
5 Alternator or Generator?
6 Repaced the ingition (key) switch recently?

well Brian let me tell you! what a PITA
1.the battery that came with it wouldn't hold a charge
2.no
3.old but straight
4.no
5.generator
6.no
I went to the closest battery store with a 6 volt, AdvanceAuto and found a new battery, it was only 2 years old and sold at a discount. Here's your sign!
It was bad but didn't realize that until I was on the side of the road again! It showed full charge until under a load, should have checked that before I left! I pulled it out and returned it and went to Battery Plus and "baby, I'm back". It was battery all the way.
the 3 elements right? air/fuel/FIRE!!
Thank you guys for all your insight and hope not to bother you anytime soon.

I never leave a store with a "new" battery until it passes a load test- - - -done MY way!

1. Load the battery to 1/2 the cold cranking amp rating for 15 seconds. For instance, load a 550 CCA battery to 275 amps.

2. Check the terminal voltage with the load still on the battery.

3. 12 volt batteries should hold at least 9.6 volts under the above circumstances, 6 volt batteries need to hold at least 4.5 volts. If the battery won't pass that test, I don't buy it!
Jerry

Where were you last Friday Hotrod? I know I learned my lesson, hopefully won't happen again.

The battery is literally the heart of the electrical system. It even determines how well the generator/alternator operates. At least half the problems with charging systems I've fixed since the early 1960's could be traced back to battery-related problems and/or loose, dirty connections. Until I am sure the battery is good and the connections are clean and tight, I don't even begin to check out other parts of the electrical system.
Jerry

I concur. 9+ out 10 times, the battery is the problem, even on modern vehicles.

You've got that right! Now on to the horn!!

I'm at my wits end! I thought I had it figured out. new battery/new fuel pump/new plugs/new coil/new condenser/fresh gas/clean carburetor and he starts quickly and idles for days!!! but when I drive more than a mile, he acts like he's running out of fuel. Give him a minute and with full choke starts right up. as you ease the choke back, he shuts down. battery is hot and tank is full of fuel. ANYBODY?

Maybe a fuel filter. I had one gave the same symptoms. It let enough through for low speed but not enough for going above 45. A partially plugged line could do the same. You might throw it in neutral and shut it down right away. Then check to see if there is any gas in the bowl.

Dennis

I forgot to mention that. also new fuel filter!

Whats the condition of your fuel tank?
is it new?

could there be a small piece of debri floating in the tank then plugging the fuel intake?

top feed tank or bottom feed tank?

new tank, bottom feed.

Did you do any work on the carb before this started? Maybe float too low? Not likely to have both electrical and fuel problems start at the same time without some changes made. I suggested earlier about shutting down right away when it happens. Maybe you could do the same by running it at 2000 RPM for a few minutes or so in your driveway then checking.

Dennis

No, I haven't done anything to the carburetor, except run some carb cleaner through it and adjust idle. Honestly sitting and starting it runs great, perfect idle speed/and charging but after a short trip up the street it won't take the gas. The fuel filter is new and clear and level. I can hear in the background a noise that sounds a little like "small block" DADDY!

any improvement, or sucking sound when gas cap removed?

that's the one thing I haven't tried but I will. that's a very good suggestion.

that didn't work either. it just will not take the gas. I guess I'm going to rebuild the carburetor and see if that does it. I don't feel like a mechanic anymore. I feel like a "technician". Just keep replacing stuff until it works!

jim911: A tip I learned the hard way. Pull the gas line off at the tank. Put into a can and watch the fuel run out. On my 52 1/2 ton it would run for a bit then slow and stop. Crud in the tank. Winter and I did not want to pull the tank out. So I rolled a bit of screen door screen up about 3 inches long and just wide enough to make 2 complete wraps. Pushed that up into the tube from the tank and now the crud can not block the out let like it did before. Use good metal screen no plastic for this. Add a clear fuel filter to get the small stuff before the pump. Made all my problems go away. Got 900 miles with no more slow down and stop issues. Might be what you have as well.

I had the same exact symptoms in my 12v 57. Turned out to be four things in combination;

The coil was/went bad. Ate the condenser (or vice versa while I was learning what the resistor was for). And my engine was well out of timing, down to a bad distributor clamp. At the same time, I had black smoke and wet plugs from running too rich because it would only run with half or better choke. Replaced the Rochester B because it tried to burn my truck down on a rural road.

The coil/condenser swap is what made the difference. Second time changing both at Advance Auto, by the way. Then I was able to tell that the carb (that I rebuilt twice) was unserviceable. AMAZING difference with the new (rebuilt) Carter YF.

I don't know that it's ever as simple as just one thing with these trucks. But I spent a lot of time chasing gremlins over it...

Best of luck,

Jim

Is it possible you have an unvented gas cap on an unvented tank.

The fuller the tank the smaller air space and the faster the vacuum will form.

Try running it with the gas cap loose (or off in a good day). If it keeps running change the cap.

They are all good suggestions guys. It sounds like Saturday is going to be a 'big" day. I'll keep in touch. Wish me luck!

Good luck.

Keep us updated, your thread will help someone else out.

While your under the hood check your vacuum advance.
Have someone goose it and see if the distributor moves.

...link...

I thought I was finished because I've got it running but no, the vacuum advance doesn't move. I drained the tank which was pretty clean. put in another filter between the tank and the fuel pump. new plugs/new wires/new coil and replaced the wires to the coil/new points/condenser/distributor cap/new voltage regulator/rotor button and 5 gallons of premium fuel and he started right up and ran like new. it's snowy and icy here so no "road" test today but my concern is that the vacuum advanced does nothing! Thoughts?

Whats your engine and carb set up?

could be a leak at either of the fittings on the vaccum line from the carb to the mechanical advanced.

check the fittings and check the line for a crack or leak

can you move(advance) the distributor by hand with out the engine running?

It should advance like in the video link I posted above(235 with a carter YF)

Rochester single barrel 7004475/yes you can move it by hand

Sounds like its timed if it starts up and idles fine.

I would check that vacuum line
if the line checks out OK your advance may be shot.

I don't know what the part number is for just the mechanical advance, when I was having distributor issues I picked up a re-manufactured distributor at NAPA auto and it came with a mechanical advance.

hopefully others will chime in with some ideals for you.

Remove the vacuum line from the advance and see if you have vacuum from the steel line while running. If yes, test the vacuum can on the advance with a vacuum checker like a Mity-vac.

Good morning everyone! Well it looks like the last thing on the list is the vacuum advance diaphragm. I did like you said and pulled the metal line off and it has vacuum going to the carburetor but when I hooked the vacuum (shop vac) to the diaphragm, I got no movement. How big a job is this to change? it looks like at glance the distributor has to come off. please say "it ain't so"! And lastly, do you ever get to "drive" these trucks??

Yes, you have to remove the distributor. You won't soon forget when you finally get to drive your truck for the first time, especially when you did the work yourself!

somehow Carl, I knew you were going to say that. I saw a much older link last night from Tiny, that said to remove the 2 nuts on the front of the diaphragm and made it sound pretty simple. I should have figured it wouldn't be. waiting for parts and next Saturday!

Did you already remove the distributor?

No

removing the distributor caused me a big headache a few years ago when I first started working on my truck.

My truck was timed and running pretty good. I removed the distributor to paint it and when I put it back in the truck wouldn't start.I had lost the timing position when I re installed it.

Now every time I removed the distributor I Take a few steps.

Before I remove the distributor I put the pointer on the ball, ...pic...

then I remove the cap and note where the rotor is pointing. It should be under the #1 or #6 plug wire position on the cap.

Now when I go to re-install it and it drops in, I make sure the rotor is in the same spot.

then re-time
For the experienced mechanics this may sound totally unnecessary but it helps me.

I'll take my time and do it but MAN! I don't want to. Thanks again for your help, I'll let you know how it goes.

I don't see a picture of the distributor.