450B not charging, checked about everything, need help!

[4x4American]

We gotta 450B that we use it constantly, it isn't charging. bossman had alternator rebuilt by john deere not too long ago, new voltage regulator. we had the alternator and the new and old voltage regulator tested the other day, and they both tested good. the guy said that our alternator wasnt charging because the prong next to the field terminal had to be grounded to the case. so he grounded it to the case. went back, put it in, still only getting 12.07volts while engine is running at any speed. any body have any ideas about what to check?

[smokydiesel]

I just fixed my alternator regulator problem with a trip to the auto parts store to get a mid 80's truck gm alternator for about $45. direct replacement, simple hook up, and you get to rip out about 50 feet of old wire. works great

[tjdub]

I just fixed my alternator regulator problem with a trip to the auto parts store to get a mid 80's truck gm alternator for about $45. direct replacement, simple hook up, and you get to rip out about 50 feet of old wire. works great

That's what I did too. It saves a lot of headache when you go with a 1-wire alternator. Even someone with my skill set can figure out how to wire it.

Those alternators are called "Delco 10si", very common, very cheap and widely used for conversions. The "si" stands for "Self Inducing" meaning that everything is integrated into the alternator and it takes care of exciting itself at a certain RPM and regulating voltage so none of the complex wiring on the machine is required, it's just a 12V lead coming out of the alternator that you can hook directly up to the battery cable going to the starter (if you don't care about your amp meter not working).

The only problem is the pulley on the current alternator won't fit. You have to buy a 5/8" wide pulley for the Delco which will run you another $25 Then you'll find that it's not the same diameter as your old pulley, so you'll need to buy a new belt too.. Also, depending on what version the factory alternator is on that 450B, you might have to make a custom mounting bracket too.

Even with all that messing around, it's still well worth the conversion in my opinion.

[Tigerhaze]

I am not familiar with what alternators come with the 450Bs. If a one-wire alternator, it is sometimes difficult to excite the internal voltage regulator due to lower operating RPMs on tractors/crawlers and the recommendation is to replace with a 3 wire version.

If not a Delco, could it be replaced with a Delco 10SI or 12SI alternator with an internal voltage regulator as previously suggested? Seems like that would make the system simpler.

EDIT: Just saw TJDub's post- sorry about the redundancy.

[smokydiesel]

I did have to open up the inside diameter of the old pulley to fit the new alternator about .040", then i just ran 1 wire from the batt post on the alt to the positive battery cable post on the starter. the belt i had on it before fit the same as the old alternator.Worked like a charm.

[JWB Contracting]

I like the 1 wire alternators, we install them on all of our going to work equipment. Basically, my dad removes almost of of the factory wiring and all we are left with is a starter wire and injection pump wire. We also go with mechanical heat and oil pressure guages.

If you did want your factory voltage guage to work, how do you wire it in?

I have opt for the fix and repair method on our current rebuilt projects instead of the cut and hack program that my dad prefers, although I cannot argue on the reliability of the 1 wire alternator. I believe he just did the 1 wire conversion on our 450G, I will check this weekend and see.

[Tigerhaze]

The problems with one wire Delco 10SI alternators are supposedly with older (70s and early 80s models). Supposedly Delco fixed that issue in newer one wire 10SI alternators.

[4x4American]

thank yawl for your input, my boss decided today to switch to a one wire voltage regulator, and it should be in soon so ill post whether it goes or it blows.

[jtrichard]

JASON ASKED If you did want your factory voltage guage to work, how do you wire it in? .................................................... if it is a VOLT meter just hook any switched hot line to it on one side and ground the other or if you want it on all the time hook it to the BATT. terminal on your key switch ....if its an amp. meter run the BATT.wire from the alt to the amp meter then to the batt. cable on the starter.................... as you can see i cant figure out how to get the green highlight on the question asked

[LeonardL]

I would like to add a foot note to what has already been said... I agree the Delco one wire is a good fix if the alternator / regulator is truly the problem. 350s and older 450s had problems with loosing connection at the bulkhead connector. This is where the wiring harness comes out of the engine compartment up to the fire wall and a connector passes it into the dash area. These come loose and or get corroded.

Another issue is the Amp gauge itself. I have had the Amp gauges on 350s and 450s go bad and cause the issue you are describing. They won't charge and will give you the idea that the Alternator / regulator isn't functioning.

Another issue is "Rodents"!!!!!!! Here in Missouri we have "Field Mice" and "Chipmunks"! They absolutely love to get in that area behind the dash panel and wreak havoc on all the wiring. Mice especially love to chew up the wiring and then usually get electrocuted in the process and smell up the entire machine. I just repaired a 350C with this very issue.

All I'm saying is before you spend a ton of money on replacing things, it might be good to just take a look at the wiring, the gauges and all of your connections.

[4x4American]

well put in a single wire voltage regulator today and it solved them problem while getting rid of a bunch of factory wiring. alls you do is connect one wire to the field terminal on the alternator and one wire to the purple wire from the connector that connected to the voltage regulator. i dont think our ammeter works at all anyways, we've done all our testing with my multimeter, we just knew that it wasnt charging because the battery always seemed pretty dead