i have a ih farmall 400,charged the battery yesterday and started it up.noticed that the amp guage is showing discharge even at high rpm.started doing some cleaning of termimals,battery,starter, generator,i don't think the generator is working.it has a 12 volt battery that is positive ground,i called a ih dealer and was told this is normal on the early 400s.i am thinking of replacing generator with a alternator is there a web site that i can go to to give me proper instructions to do this converson? is it possible to change this with the positive ground?and how much wiring do i have to change?i am thinking it would be less expensive then having the generator and volt regulator replaced.any help from this group is good help.thank you,john
amp guage discharge
- Thread starter jiw01
- Start date
John *.?-!.* cub owner
501 Club
before you start throwing money at it, follow this trouble shooting chart.
Dusti Snider
501 Club
Ground the field termianl on the generator and see if it charges, that'll tell you whether the VR is bad or the generator. Your tractor should be 6volt. Has it already been converted?
Under edit...John typoes faster than I do
Under edit...John typoes faster than I do
john,dusti thank you for your responce.i will follow these instructions in the morning.dusti,as much as i know from the preveious owner he told me it was 12 volt when he got it,also the ih dealer said the early 400s were 12 volt positive ground,but when i had the generator off to clean braskets i noticed some numbers on it,can't remember them all but there is a 6 space 71.does that tell me 6 volt? thanks again
Some of the early 2-volt IH tractors were positive ground. But I believe all gas powered 400s came from the factory with 6-volt. The 450s came 12, maybe not all of them.
The original generator was 1100531. The tag should be black (12-volt were red). The numbers stamped into it should be 1100531, followed by a few spaces, followed by a date code of digit, letter, digit, digit. The first digit is the last of the year, the letter is the month, the last 2 digits are the day of the month. So 5C21 would be March 21, 1955. Letter I was not used so J=September . . .
Your generator may have been changed out. Rebuilders tend to take a one-size-fits-all approach.
The original generator was 1100531. The tag should be black (12-volt were red). The numbers stamped into it should be 1100531, followed by a few spaces, followed by a date code of digit, letter, digit, digit. The first digit is the last of the year, the letter is the month, the last 2 digits are the day of the month. So 5C21 would be March 21, 1955. Letter I was not used so J=September . . .
Your generator may have been changed out. Rebuilders tend to take a one-size-fits-all approach.
good morning jim,did not know that there was a 2 volt system,good to know.so if the 400s were 6 volt and mine was changed to 12 volt then should it be negative ground?this is what is confusing,also i checked the numbers on the generator.1100305 then under that 6 space(there is no letter)71.if i was to turn the battery to neg ground would that cause any problems ? how can i test the generator off the tractor?thank you,john
John *.?-!.* cub owner
501 Club
I believe that was a typo, and should have been 12 volts, not 2. A 2 volt system would require battery cables about half the size of your arm.jiw01":1ddork8y said:
You can get rough test off the tractor by connecting 12 volts to the A terminal and grounding the F. It should run like an electric motor, though not real fast.
According to the book, that is a 12-volt generator. It was used on the 450 starting with serial number 11084. Prior to that Diesels and LPs were 12-volt but used a different generator. A typical Delco Generator tag looks like this (picture borrowed from the Cadillac-LaSalle website, ignore the question marks). I don't know about your "6 71" stamps, unless it was added by a rebuilder.
The 400/450, even in 12-volt, were positive ground systems. For the most part, simple generator systems don't care much* which way they are grounded. Just polarize the generator after installing the battery.
A couple simple generator checks can be done off the tractor, don't guarantee completely proper operation. First, I'd look at the brushes to see if there is reasonable chance it works. Take the band off if there is one or look in through the end frame. If that looks OK, Try a motoring over test with a good battery.
1) Attach a ground lead from the battery to the generator frame.
2) Ground the F terminal.
3) Attach a hot lead to the A terminal. Generator should motor over.
4) Remove the ground from the F terminal. Generator should speed up.
* Original regulators used contact material based on polarity and last longer if used properly. Solid state electronics (transistor radios, breakerless ignitions, etc.) depend on specific polarity.
The 400/450, even in 12-volt, were positive ground systems. For the most part, simple generator systems don't care much* which way they are grounded. Just polarize the generator after installing the battery.
A couple simple generator checks can be done off the tractor, don't guarantee completely proper operation. First, I'd look at the brushes to see if there is reasonable chance it works. Take the band off if there is one or look in through the end frame. If that looks OK, Try a motoring over test with a good battery.
1) Attach a ground lead from the battery to the generator frame.
2) Ground the F terminal.
3) Attach a hot lead to the A terminal. Generator should motor over.
4) Remove the ground from the F terminal. Generator should speed up.
* Original regulators used contact material based on polarity and last longer if used properly. Solid state electronics (transistor radios, breakerless ignitions, etc.) depend on specific polarity.
John *.?-!.* cub owner
501 Club
To answer the part about the alternator, positive ground 12 volt alternators are rare, if they even exist. But to change to negative ground merely involves reversing the wires on the amp meter. Here is a link to wiring diagram for converting H or M to alternator, the wiring on your 400 should be similar. You will have to make your own mounting brackets.
http://s101.photobucket.com/albums/m46/ ... _22_08.gif
http://s101.photobucket.com/albums/m46/ ... _22_08.gif
Dusti Snider
501 Club
John *.?-!.* cub owner":1vwr83bw said:
Don't forget to swap the wires on the ignition coil...
jim, john,again thank you for the valuable information.i tryed all all tests,its the generator so leaning toards the alternator idea.sorry for the slow responce, got torn away form this project to retreave a crying cub longing for my ownership,whitch brings up another question.this cub has a tag, little hard to read,i see #10452 then below is 1800.where can i find it's year of production? also it has a 8 volt battery,on whitch setting do i use to charge,12 or 6 volt?
Dusti Snider
501 Club
Your Cub is a late '47 model, the first year built. 1800 is the engine rated RPM's. The 8 volts battery should be charged on 6 volt.
I think you'll be very pleased with the alternator on your 400.
I think you'll be very pleased with the alternator on your 400.