model 40 alternator problem

kevencyr · Post by **kevencyr** » Sat Jun 04, 2016 12:55 pm

my 12 volts alternator failed so I got a new delco 85amp. my problem right now is that my volt gauge is pegging and notice my battery becoming really hot that I can hear it leaking, was lucky it didn`t blow up. would someone have any idea what going on. I think it related to a voltage regulator, but I taught it was in the alternator, not sure anymore. also, anyone got a proper 12 volts wiring diagram. thank you

Stan Disbrow · Post by **Stan Disbrow** » Sat Jun 04, 2016 6:23 pm

Hi,

Some alternators have built-in regulators. Some use external ones. Obviously you have a regulator problem as the alternator is always full on.

The wiring diagrams for a 40 are for 6 volt positive ground systems with generator as mechanical regulator. So, no good to go with what you have.

I would be going for a different alternator known to have an internal regulator and cut-out which simply hook to the positive side (of a 12v negative ground) battery. That way, wiring is easy: One #12 wire!

Stan

gregjo1948 · Post by **gregjo1948** » Sun Jun 05, 2016 6:07 am

I'm thinking the Delco should have an internal regulator. Maybe you got a faulty alternator and should inquire where you purchased it to see, if it has a regulator and have it tested.

kevencyr · Post by **kevencyr** » Mon Jun 13, 2016 4:25 pm

ok, so yep, regulator was into the alternator and damage. so the person fix it and also for some reason decided to modified the alternator with just 1 wire. so my dad installed it and it doesn't make sense with the gauges operation. is there some one that could tell me how to wire my bulldozer properly, he told me he had a volt meter, amp meter, switch and push/pull starter button + battery and starter. did some digging, can't find anything making sense to me. thanks
p.s. i'm doing this for my dad and he live 4 hours away from me, so my troubleshooting is on the phone, not easy. thanks

Post by **Lavoy** » Mon Jun 13, 2016 11:42 pm

A 40 never had an alternator, so you are not going to find any information about it. Any of the two cylinder crawlers that had an alternator had it put on by someone later in it's life and converted it to 12 volts.
Lavoy

kevencyr · Post by **kevencyr** » Tue Jun 14, 2016 2:53 am

so, any wiring diagram with a wire coming out of the alternator with all my component included would be ok

Stan Disbrow · Post by **Stan Disbrow** » Tue Jun 14, 2016 4:47 am

Hi,

A one-wire alt, has one wire going straight to the batt. So that is easy.

You need another wire from the batt to the input side of the key switch. Make sure that the alt wire goes to the batt and not the switched side of the key, or you won't be able to shut the machine off.

The voltmeter has one wire to ground, the minus wire, and one wire to the switched side of the key, the plus wire. Get that backwards and it will deflect the wrong way and might damage the pointer. It does need be on the switched side of the key. That way, it will turn off when the key is in the off position.

The amp meter goes in-line between the alt and the batt. That has two ways it can be wired in. The correct way it will deflect to the charge side when running. If it winds up backwards, just swap the wires on the ammeter. Actually, with a voltmeter, one doesn't need an ammeter. If the voltage rises after starting, alt is working. Conversely, if the voltage drops while running, it isn't charging.

The ignition hooks to the switched side of the key. You need to either add in a ballast resistor between the key and the 6v coil. Or change to a 12v coil. Or burn up the 6v coil. The output side of the coil primary goes to the points just as it did originally.

Pos cable from batt to starter, and the pull rod works the same switch on the starter as it did originally. Neg cable to ground, of course.

Stan

kevencyr · Post by **kevencyr** » Tue Jun 14, 2016 9:05 am

ok thanks, that will help very much, i also found a diagram online last nigh but not as detail as you told me. actually going to my dad's in a few weeks, will try that. thank you again.

jtrichard · Post by **jtrichard** » Tue Jun 14, 2016 9:52 am

Hi I would NOT run the alternator wire through the amp meter as the ALT. is high output and your amp meter will most likely be pegged all the time IF it will even put up with the high amps ....Also I would hook the alt; wire to the main battery cable at the starter NOT the battery (less corrosion problems) Your main feed to the Key switch should already be there

Stan Disbrow · Post by **Stan Disbrow** » Tue Jun 14, 2016 11:48 am

Hi,

Good point. If that ammeter is the original, it pegs at around 20 amps. You have to match the ammeter to the alternator as far as amps go. Another good reason to abandon an ammeter for just a voltmeter.

Stan

Post by **Lavoy** » Tue Jun 14, 2016 2:09 pm

Any wiring diagram you will find will not have anything to do with an alternator, so I would stop looking at them, they will not help for what you are trying to do.
Lavoy

kevencyr · Post by **kevencyr** » Tue Jun 14, 2016 3:59 pm

i found a wiring diagram for a ford 8N with 12 volt conversion. got some point, coil, terminal block, voltmeter, key switch, starter button, starter and a battery in the schematic. i'm pretty sure it would work since it got the same component i got. still will make a schematic with Stan info and compare. thanks

Post by **Lavoy** » Tue Jun 14, 2016 8:51 pm

Okay, that will get you a starting point, I was under the impression you wanted one for a Deere.
Lavoy

kevencyr · Post by **kevencyr** » Wed Jun 15, 2016 2:34 am

you are right, it's for my Deere but it think with the same components and since its had an alternator on it when i got it, probably the people before didn't wired it properly. so with all the info and some guidance here and there, i should be able to removed everything and start over. I'm hoping anyway. will see in a few weeks.

Post by **Lavoy** » Wed Jun 15, 2016 8:18 am

That's what I would do. Throw away every wire on there, start from scratch, and then you know you have found the problem.
Lavoy

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model 40 alternator problem

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