8 Volt Battery
Fleet Owner
Joined: Jul 2004
Posts: 27,299
Likes: 1,059
From: NM
Sounds like the generator isn't producing anything, or the regulator isn't telling it to. Pt the battery on a charger overnight and measure voltage at the battery with the engine running at 2000 RPM or so.
I'll have the Roast Duck
Joined: Jul 2002
Posts: 9,622
Likes: 110
From: Northshore, MN
With my block heater plugged in for a few hours, my Golden Jubilee will fire with a squirt of ether at -20F. So I have no qualms with a 6v battery at cold temps. I plan to "upgrade" with a red optima in the future. BTW, I agree with Ross.
Post Fiend
Joined: Apr 2002
Posts: 19,311
Likes: 97
From: Waterloo, Iowa
Most people today are familiar with an alternator charging system, they provide charging current at idle. Not so with a generator. The cutout - and that's what it is, kicks at about 1300 (generator RPM) or so. So the battery has to pick up the slack at low engine RPM. It doesn't take much to tip the scales, a couple long cold cranks, short trips with stop and go driving, a little rust and corrosion here and there, flip the headlights on, she's done.
CCA is important for easy starts but also, sufficient reserve capacity. Use the biggest and heaviest battery that will fit and charge it up thoroughly before installation. Generators do not like resistance in the connections and grounds. Neither do alternators as far as that goes, but generators are already behind the eight ball so everything has to be squared away.
Did the GEN light illuminate, or is this an ammeter?
CCA is important for easy starts but also, sufficient reserve capacity. Use the biggest and heaviest battery that will fit and charge it up thoroughly before installation. Generators do not like resistance in the connections and grounds. Neither do alternators as far as that goes, but generators are already behind the eight ball so everything has to be squared away.
Did the GEN light illuminate, or is this an ammeter?
Lead Driver
Joined: Jul 2011
Posts: 6,599
Likes: 34
From: Rockingham, VA
Senior User
Joined: May 2014
Posts: 465
Likes: 2
From: Moorhead MN
I'd look at your generator next. Very common for them to get old/wear out on these trucks. A rebrush/rebuild could be done yourself or reasonably at a reputable shop in your area. Edit: Just saw all the replies, don't know why they weren't showing..
Post Fiend
Joined: Apr 2002
Posts: 19,311
Likes: 97
From: Waterloo, Iowa
Yep. It's pretty common for people take great pains on the motor rebuild, but then reinstall a worn out generator and then bitch they aren't reliable. They will not handle anything above 6 grand but other than that they work fine. Heavy *******s though!
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Believe Nothing
Joined: Jun 2004
Posts: 7,516
Likes: 403
From: W. Central FL.
Perhaps Clint's truck just needs driven at speed for an extended period
Mountain Pass
Joined: Jun 2013
Posts: 154
Likes: 9
From: Chattanooga
I just saw this
Back in day, I drove my 52 F-1 every day. It was my only transportation to HS and college and to work. It had the 6 volt positive ground system in it the whole time I was driving it daily (1983-1990).
I had an 8 volt battery in it the whole time. I adjusted the voltage regulator up to 9.2 volts the only reason was so it would crank easier on both extremely cold and hot days.
I used 6 volt bulbs. I don't recall them blowing that often. I probabably changed headlights once in that time. I don't recollect changing the dash lights or the parking lights. I did go through a lot of taillights. Brake lights to be more specific.
I had no resistors in the gauges, nor the coil. They were fine. The heater ran fine too as did the electric wiper motor. My pickup originally had vacuum wipers but I found an F-3 in a junkyard with electric wipers and I swapped them out.
Keith
Back in day, I drove my 52 F-1 every day. It was my only transportation to HS and college and to work. It had the 6 volt positive ground system in it the whole time I was driving it daily (1983-1990).
I had an 8 volt battery in it the whole time. I adjusted the voltage regulator up to 9.2 volts the only reason was so it would crank easier on both extremely cold and hot days.
I used 6 volt bulbs. I don't recall them blowing that often. I probabably changed headlights once in that time. I don't recollect changing the dash lights or the parking lights. I did go through a lot of taillights. Brake lights to be more specific.
I had no resistors in the gauges, nor the coil. They were fine. The heater ran fine too as did the electric wiper motor. My pickup originally had vacuum wipers but I found an F-3 in a junkyard with electric wipers and I swapped them out.
Keith
Senior User
Joined: May 2014
Posts: 465
Likes: 2
From: Moorhead MN
This reminds me, I had mentioned thinking about a 12V system to my great-uncle. He was very adamant that was not necessary, telling me that if he knew it would be really cold the next morning for his morning work with the cows, he'd hook up the trickle charger, and, even when it was 30 below, he had no trouble starting it, especially if he used the coke. I don't doubt this one bit. These trucks may crank slow with 6 volts, but when they catch, they catch.
Fleet Owner
Joined: Jul 2004
Posts: 27,299
Likes: 1,059
From: NM
What I've found makes a huge difference for starting is a modern gear-reduction, permanent magnet starter. The field coils on original starters suck a bunch of current, and they crank slowly because of the direct gearing to the flywheel. Combined with the alternator that instantly recharges the battery, it's a really robust system. I realized last summer that my battery is 10 years old... I'm tempted to replace it "just because", but it starts great even with temps in the mid-20's.
Senior User
Joined: May 2014
Posts: 465
Likes: 2
From: Moorhead MN
What I've found makes a huge difference for starting is a modern gear-reduction, permanent magnet starter. The field coils on original starters suck a bunch of current, and they crank slowly because of the direct gearing to the flywheel. Combined with the alternator that instantly recharges the battery, it's a really robust system. I realized last summer that my battery is 10 years old... I'm tempted to replace it "just because", but it starts great even with temps in the mid-20's.
Fleet Owner
Joined: Dec 2000
Posts: 25,410
Likes: 5,420
From: Central PA
What I've found makes a huge difference for starting is a modern gear-reduction, permanent magnet starter. The field coils on original starters suck a bunch of current, and they crank slowly because of the direct gearing to the flywheel. Combined with the alternator that instantly recharges the battery, it's a really robust system. I realized last summer that my battery is 10 years old... I'm tempted to replace it "just because", but it starts great even with temps in the mid-20's.