Hi, I'm new to this board and apologize for jumping right in with a problem. But I just came in from working on my truck and I'm really exasperated. She's a 49 F-2, not fancy but not too shabby either. She was converted to 12 volt sometime in the past, before I bought her, and that's where my problem is. The alternator whacked on me last year, and I had to replace it. Before and after that happened the indicator showed a constant slight discharge. I killed a battery; fine, I replaced it four days ago. Drove it just a bit, in the evening with the headlights on. Went to crank her over this morning- she gave one mighty effort, and the battery died.
All the connections look good, no rust buildup. I'm thinking it's something faulty in how the conversion was done, but would really appreciate the thoughts of other people who have dealt with these old trucks.

 

I think maybe do a draw-test..see if something is staying on,killing the battery.
Maybe start disconnectig things till the draw goes away...look at that circuit.

 

Welcome to the board!

What kind of alternator was used? It seems to me alt's some need a diode in one of the wires to prevent back-flow when not running. If your ammeter is active while the truck is off, unplug the alternator and see if the draw stops.

 

?????? Welcome to the group!!!!!!
alternator with or without regular
Wiring original or aftermarket
column original or other
engine
need more details on what you have, have a great day,chuck

 

Wow, wasn't expecting a response so fast, thanks for taking the time to do that. OK, let's see...
The wiring is mostly original, with a couple of newer lines going to the taillights (already tried cutting those to check for shorts, no luck). It does have the original column, and the engine is a flathead 6. The volt regulator is bypassed, presumably the alternator has an internal one. I don't show a drain when the engine is off. The only aftermarket device on it is a heater installed several years ago- currently dismantled in the shed for repairs.
It was basically a one-owner truck when I got it (guy got it from his dad, who bought it new) and he took good care of her all these years. Drove her around town until he sold her to me. I suspect that any quirks she had were so subconsciously compensated for the he didn't think to mention them. It's just rough because it's my dream truck and other than a turn in a small-town parade and a few errands to the feed store, she's been sitting since I bought her.
Oh, a new rabbit trail I'm chasing down, my meter show the battery to be fully charged, and she cranked up fine this afternoon, after acting like the battery was nearly dead just yesterday.

 

LOL, I'm betting that the Previous Owner forgot to run the battery wire backwards thru the ammeter loop, when converting it from 6v positive ground to 12v negative ground! The "slight discharge" you see is really a slight positive charge! i.e., there's nothing wrong except you don't drive it enough.

With the truck off, turn on the headlights and see which way the ammeter swings. If it goes towards Charge, it's reading backwards.

 

Alas, it shows a discharge with the lights on. Now that you mention it though, the PO did mention that he made it a habit of firing her up pretty often. Other than battery trouble, the reason I haven't had her out much is because I was afraid I'd get stuck somewhere- happened once, right before I replaced the alternator. Fortunately, I'd just bought into AAA, and they were battling over who would get to come pick her up!
So I'll see if cranking her over every day is the trick. Whew, hope gas prices come down soon.

 

I always try to park my truck on a slight downward incline. That way if it decides it doesnt' want to start I use gravity and pop the clutch. I also have two teenage boys for the same purpose. I run into problems sometimes with my F-2, it doesn't always wants to start. It's just one if it's few quirks. BTW, mine is 6V stock.

 

the first thing to find out when it don't start is the battery dead or not,they don't charge themselves back up
if the battery is not dead,how is ground cable run,it should go to the engine then another from engine to frame,then another from frame to cab all conections need to be clean and tight
next to the positive side,the cable to starter solenoid,what type solenoid is being used
was it converted to newer two small post type or one post

what type of alternator,is it GM one r two wire?

 

If the battery just loses charge over a period of a week, it's a goner. It sure wouldn't hurt to go thru the whole system like rtbaker says, but if it works fine one day and is a no-go the next, it's almost certainly the battery. It could have died when the alternator wasn't charging it properly.

 

I'm going to check into the solenoid when the weather improves a little- pretty sure it's the original, and the engine does try to start... I'll check the ground cables too, though the only thing that seems to jump out there is the cable running from the flathead to the firewall seems pretty new, the screws on the firewall end too. It's a two wire alternator.
This morning I went out to check on them, and decided to turn her over first. Yesterday she started right up (by which I should add that I have to keep my foot on the gas for awhile until she decides to run on her own, don't know if that's significant) and I drove her a bit around the yard. But when I went to try it just now, she gave a sluggish grumble then nothing. That's the way it goes with this truck. When I try again this evening she'll probably start right up. I should add, I killed the engine once while driving yesterday and it started right up again. I know, I think alternator too, but I just replaced the thing ..
When I initially turn the key, before I hit the starter button, the needle drops just a bit to the discharge side but from what I've read that's normal(?) Didn't run the lights on yesterday. Just drove her across the property... and it's a new battery.
It looks like the old owner kept things pretty much as they were unless need warranted a change, like, there are modifications to the carb. .
Thanks for the park-downhill tip bobj. It's pretty flat here but I can find a spot.

 

One more place to check is the stud on the starter. Check the stud, clean with a wire brush, sand the cable end with a piece of sand paper. These spots are notorious for getting dirty. You could also have an internal problem with the starter, where the stud connects to the bars that lead to the fields of the starter.

Just a couple of places to check.

 

You mentioned that you had a new battery. How new is new? less than a year?
Batteries can and will do some funny things. A battery with a shorted cell can cause problems as you describe. Typically you don't see it so much on newer batteries.

There's a chance that the starter could be dragging occasionally. A dragging starter can also act like a dead battery.

If you can't find a slight hill to park on I'd be glad to ship you a couple of teenage boys. They're fine strapping young lads who are plenty tough enough to push start an old Ford truck. I'll even pay for the shipping

Bobby

 

LOL, thanks Bobby, got one of my own actually, more interested in guitars than my truck!
Dragging starter, and the stud on the starter. I'll dig out the coveralls (again) and see what I come up with (again)
And hey, I really appreciate you taking the time to help me with this!

 

Alright, going to risk sounding like a total bonehead here (bearing in mind I've never scrubbed a starter before) When I went after that screw on the starter, my truck made some crazy noises that made me jump (adjusting the ice on my head now), apparently my scrubbing activated the starter- I watched more closely as I drew the brush across and yep, serious sparks whenever the wire bristles contacted the starter. Is that normal? If so, should I just disconnect the battery before I try taking that bolt off?
And while I'm looking like a complete dunce, is it normal for a truck that's been converted from a generator to an alternator to never show a charge on the gauge?