Hey guys!

Sorry for the newbie question but i figured this is the best place to ask.

LOOKING FOR:
Alternator - 65Amp Autolite C8TF-10300-A or equivalent
Regulator: C6AF-10316A

BECAUSE....

BACKGROUND:
1968 F850 Super Duty Fire Truck (Pumper) with the 534. 4500 miles on it.
Ran fine. Could drive the thing 70 mph. BAtteries were kind of old and we charged them after adding water. Several months later, batteries were dead, moved the thing to my house but had to jump it and i don't thing the alternator could charge them enough. About 10 mins from the house i had the headlights on (brights accidentally) and the volt gage on the dash started jumping up and down and the lights were flashing (maybe alternator or regulator dying?) Tried to charge them at the house with a napa charger, and that didnt work. Jumped the thing but it go REALLY hot started melting the cable clamp coating. Something fried i think, because now the little red light next to the ignition key doesn't come on when you turn it on and there seemed to be NO spark.

WHAT I TRIED:
1. Checked for fuzes. Couldn't find inline fuzes, and panel fuzes checked out ok.
2. Checked spark at coil. NONE.
3. Through Optima from Jeep in there. Hot wired coil straight from battery. Little red light now turns on next to ignition switch. When i hotwire coil, the regulator "clicks" . Thing Runs!
4. BUT!....Voltage at battery seemed to be dropping (in the 11.9 V range). Didnt seem to be charging. Voltage out of regulator was ZERO. Buddy suggested these old ford regulators are crap and thats probably the issue. BUT, maybe im retarded and just needed to rev the engine up more....In that case, there's still something messed up because i have to hotwire the coil....

FINDING NEW PARTS....or NOT!
Parts store couldn't find an alternator very easily. Finally found a 65 amp supposedly they would have to order for 130 bucks!.

OPTION 1: The regulator seems to be in something like a 67 mustang. Little gray box with 3 wires to a connector. An ALTERNATOR for something like this at 65 Amps is $45 and has a shorter distance between mounting points. I could get this alternator (or one similar with an INTERNAL regulator) and modify the tensioning bracket.
OPTION 2: Someone tells me where to find a cheap *** one of these ACTUAL alternators, and regulators
OPTION 3: Open alternator, clean it, and clean connections in engine bay. Put it back together, check things out more - IN PROCESS...
OPTION 4: Drink more

Anyway, i know that was a long story, but basically looking for direction to get these parts or a wiring diagram (would be GREAT!) or just some general guidance. ANy help is appreciated.

Cheers!

 

Well, a couple of thoughts here. Don't take offense at my suggestions.
Has the alternator been tested?
Has the regulator been tested?
There are a few chain stores that won't sell you parts for anything over a 1 ton truck. (Autozone...cough.....cough....) What store are you trying to get parts from?
If you are sure the alternator is bad, there are some places that will allow you to send in the old one, they will rebuild it and then they'll send the exact one back to you.

 

See answers below (in red) to questions and the following UPDATE.

Well, a couple of thoughts here. Don't take offense at my suggestions.
I wont. i appreciate them.

Has the alternator been tested?
Not at a parts store. I took it in to Oreilleys and the cross-referenced alternator number they had said it needed to be ON THE VEHICLE! No help there :

BUT....on the vehicle i have tried the revving up to 2K rpm and checking the voltage ....its at like 8V coming out of the alternator i think it was and like 12 at the battery.

Has the regulator been tested?
Not sure how to test it except measure its input or output when running. I want to say it WAS gettting the 12 volts in not sure about out. I might try that again. But i thought i remembered thinking it was ok.

There are a few chain stores that won't sell you parts for anything over a 1 ton truck. (Autozone...cough.....cough....) What store are you trying to get parts from? Oreilley's and Autozone. No carquest or Napa nearby. Napa ended up giving me the same part number basically though and for approximately $150

If you are sure the alternator is bad, there are some places that will allow you to send in the old one, they will rebuild it and then they'll send the exact one back to you.
I found a place locally. thanks for the tip. havent taken it to them yet because it seemed as thought there was a short elsewhere.


UPDATE: Was getting continuity between power and ground at the alternator. I thought the alternator had grounded itself out. I disconnected the power to the alternator and the alternator didnt show cont. anymore so i figured it was int he supply line. I isolated part of the cable to the alternator and the regulator. Seemed as thought he short must be coming from somewhere upstream, passed the regulator. Seems as though my fuze box had sections continuous or nearl continuous to ground, so i started pulling fuzes (allthough the fuzzes were good) to see if anything upstream of the fuzes was gorounding the fuze box. Seemed as though the dome and emergency light circuits may have shorts.

From what i can tell there still isn't power to the coil, unless i hotwire it) which i understand is bad because it should only see 12 V at start.

I am starting to think it is the ignition switch.....i think ALL 3 original problems kind of go back to that part:
1. Little light next to switch goes out
2. Coil doesn't get power
3. Alternator doesn't charge system because Volt Regulator isn't getting power from iginition switch (i think it is part of the circuit).

GOOD NEWS:
My landlord's (neighbors) wife says," i grew up with a dad that had cars everywhere and i hated it....now i have a frickin fire truck in my driveway. Maybe this is supposed to get me over those issues i had as a child"

I say, "i have always hated figuring out electrical issues on cars. Maybe this is supposed to teach me something. "

Ha!

 

Some of these old trucks would burn the wires off the back of the ignition switch, they use to make a replacement plug to replace the bad one. This truck may or may not have fuseable links , usually located at the starter solenoid. If you have power coming to the F terminal of the alternator and aren't getting out at least 13.5 volts at the bat terminal of the alternator . This usually points to the aternator itself. If there is no power to the field (F} terminal this points to the regulator. Most of the electronic regulators have a wire that has power when the ign switch is on , one that has 12v from the battery for sensing voltage, and the {F} wire going the the field terminal of the alternator voltage varies with output demands. To check the alternator a hot jumper wire connected to the field terminal will let the alternator produce full output.

Have A Great Day --- Hotwrench

 

toymachine, if you find you do need an alternator, PM Archion, he has good sources on larger truck parts. The regulator sounds like the normal Ford style of that era, there are solid state replacements. Archion may even be able to hook you up with a 3G alternator.

 

I'll give another vote to modernize the charging system on this.
Ford has some good alternators that could be scavenged from a salvage yard. If the requirements aren't too hard on the alternator, you could even use a (gasp, argh) Delco internally regulated replacement. Also consider switching to a voltmeter instead of the (I assume) factory ammeter.