12v to 6v conversion Farmall 140

[worm12ga]

I'm partially restoring a Farmall 140 for my wife's employer. I'm not going for 'parade' quality, it is a working tractor that will be used several times a week on the farm.

Someone converted it from 6v to 12v at one point, but they did a hack job. Loose wires, unconnected wires, splices so ugly I can't believe they got paid for the job.

The owner wants to go back to 6v. What I want to know is how the whole system [u:fcc40d08c8]looked[/u:fcc40d08c8] originally. I have wiring diagrams, and I know what parts I need to find in the barn or buy, I just need to see where everything originally was routed. The battery is currently under the seat, the alternator is not even hooked up, the starter switch lever (12v starter) is a 'custom' piece of scrap metal someone attacked with an angle grinder.

I did try to search, but did not find what I need. I'm open to suggestions about whether I should just clean up the crap wiring job and leave it 12v, or go full-on and get it back to 6v. Reliability is more important than appearance on this machine.

 

[worm12ga]

I forgot to mention it is a 1959 model (I was told).

 

[rvirgil_KS]

Since you say reliability is more important than appearance and you already have the 12 volt battery and alternator, I would keep the alternator and clean up the wiring. My opinion for what it's worth.

 

[Janicholson]

caseih.com site has parts diagrams as do the repair manuals. The basic wiring can be found here Bob M wiring diagrams in archives. Jim

 

[worm12ga]

Thank you for your opinion. I was leaning that way already for this season. Maybe next winter I can go to town on it, but for now they need to start cultivating the fields. I'm still open to other opinions, and especially good photos of the original wiring, battery mounting, etc.

 

[DeltaRed]

Leave it 12. Just rewire/clean up to the best of your ability.Make it 'clean' and reliable. Who cares whether or not it is
"original"/factory perfect on a 'worker'.

 

[worm12ga]

(quoted from post at 07:57:47 04/06/16) caseih.com site has parts diagrams as do the repair manuals. The basic wiring can be found here Bob M wiring diagrams in archives. Jim

I have the manuals on paper, including the wiring diagrams. What I haven't found are good pictures of the wiring on an actual tractor. I can make the wiring work no problem, I'm just trying to keep/return it to as original as possible while keeping it reliable. More than one hack 'mechanic' has messed with this thing.

 

[worm12ga]

(quoted from post at 08:00:31 04/06/16) Leave it 12. Just rewire/clean up to the best of your ability.Make it 'clean' and reliable. Who cares whether or not it is
"original"/factory perfect on a 'worker'.

Alright, 2 opinions agreeing with my initial instincts works for me. Gonna get over to the farm and start cleaning this mess up. Thanks.

 

[worm12ga]

The frustrating part is I can't get a clear answer from anyone WHY things were modified. I feel like the 12v modification was to cover up another problem, but have no idea what it was. Spending wayyyyy too much time cleaning up other people's messes on this farm.

Sorry for the venting.

 

[Charlie M]

I got my 47 Cub like that with 12 volts and the crazy wiring. I think someone bought a wiring harness and got one for a newer machine that has safety switches, etc and the result is wiring that goes no where. Wiring on 12 volts is pretty simple and even simpler if its a mag. I would just clean up the wiring if it were mine.

 

[Jim Becker]

The most common reasons for converting seem to be:
- generator quit and they didn't know how to put new brushes in.
- starting problem due to worn out starter that was starting to drag and the fix was to double the voltage.
- starting problem due to worn out engine and the solution was to spin it faster by doubling the voltage.
- battery went bad and they couldn't find a 6-volt battery.
With your description of the wiring, any of these explanations seems likely on this tractor.

Sounds like they couldn't find the right size 12-volt battery either so they moved it under the seat. By the way, the original battery box needs to be properly bolted in to brace the control panel. Otherwise, movement of the panel reduces control of engine speed and hydraulic operation.

The advantage of putting wires back where they originally were is that IH went to the trouble of locating the wires where they were out of the way and protected from normal activity. As far as finding original wire routings, the original parts catalog actually has an excellent diagram. It can be found on the CaseIH site. Look for diagram "ELECTRICAL, STARTING & LIGHTING, BATTERY IGNITION, 6V, FOR 140 SERIES TRACTORS W/ S/N 26800 & BELOW". There are a few pictures that show parts of the wire routing in the PM manual (and probably the owner's manual). You have to look through for the 140 pictures.

http://www.cleancomputes.com/Cub/Cu...58//Preventive Maintenance Manual 6-13-58.htm

 

[gene bender]

Should have seen the mess on a Cub i bought was12 alt, removed the fan shroud and put a car motor powered fan on then soldered a piece of threaded rod to the start button on the starter to hook up batt then one sw to turn on Alt so it would work then another sw to run fan and then turn sw to start the tractor. Now its all original and works just fine but what a mess when all it needed was the starter refreshed brushes ect.

 

[David G]

If you want it reliable, leave the alternator, rewire cleanly and be done.

 

[worm12ga]

(quoted from post at 08:38:33 04/06/16) The most common reasons for converting seem to be:
- generator quit and they didn't know how to put new brushes in.
- starting problem due to worn out starter that was starting to drag and the fix was to double the voltage.
- starting problem due to worn out engine and the solution was to spin it faster by doubling the voltage.
- battery went bad and they couldn't find a 6-volt battery.
With your description of the wiring, any of these explanations seems likely on this tractor.

Sounds like they couldn't find the right size 12-volt battery either so they moved it under the seat. By the way, the original battery box needs to be properly bolted in to brace the control panel. Otherwise, movement of the panel reduces control of engine speed and hydraulic operation.

The advantage of putting wires back where they originally were is that IH went to the trouble of locating the wires where they were out of the way and protected from normal activity. As far as finding original wire routings, the original parts catalog actually has an excellent diagram. It can be found on the CaseIH site. Look for diagram "ELECTRICAL, STARTING & LIGHTING, BATTERY IGNITION, 6V, FOR 140 SERIES TRACTORS W/ S/N 26800 & BELOW". There are a few pictures that show parts of the wire routing in the PM manual (and probably the owner's manual). You have to look through for the 140 pictures.

http://www.cleancomputes.com/Cub/Cu...58//Preventive Maintenance Manual 6-13-58.htm

Thank you for all of that input. The 'story' i was given was that the alternator wasn't charging (I believe it was never actually hooked up) and the battery position was changed because the charging cables were shorting out on the battery box. From what I understand, they were charging the battery at night, and running solely on battery power out in the fields!

 

[worm12ga]

I skimmed through the manual you posted, it looks like the paper copy I have. Neither provide a picture of how the wiring was routed. I tried, but failed to get anything off of the International website.

I'm sticking with 12v for the season, and replacing the s!@$ wiring that was spliced in. I'd still like to see how the wiring is supposed to look so I can get the battery back where it belongs. Owner is willing to pay for proper battery, wires, etc.

 

[BarnyardEngineering]

OEM style wiring harnesses can be obtained from companies like Brillman and Agri Services. You might even be able to get one from your local CaseIH dealer. Either way that would help you figure out routing because the length of the wires limit where they can go.

One big reason for converting that hasn't really been alluded to is cost. For less than the cost of having someone professionally rebuild the generator, you can have a generic Delco 10SI alternator and a small 12V battery.

The bad part is most people go crazy with rewiring the tractor when it only requires a couple of minor changes with no actual cutting of the factory wiring harness.

6V is fine, though. Nothing wrong with wanting to make/keep it original.

 

[worm12ga]

(quoted from post at 10:50:11 04/06/16) OEM style wiring harnesses can be obtained from companies like Brillman and Agri Services. You might even be able to get one from your local CaseIH dealer. Either way that would help you figure out routing because the length of the wires limit where they can go.

One big reason for converting that hasn't really been alluded to is cost. For less than the cost of having someone professionally rebuild the generator, you can have a generic Delco 10SI alternator and a small 12V battery.

The bad part is most people go crazy with rewiring the tractor when it only requires a couple of minor changes with no actual cutting of the factory wiring harness.

6V is fine, though. Nothing wrong with wanting to make/keep it original.

Would it be wrong to assume there are functional used 6v generators on the market, since so many people go to 12v? I see used ones for sale, without guarantee that they are working units. The new ones are just too expensive in my opinion.

 

[Jim Becker]

(quoted from post at 12:41:50 04/06/16) I skimmed through the manual you posted, it looks like the paper copy I have. Neither provide a picture of how the wiring was routed. I tried, but failed to get anything off of the International website.

You need to look closer. In this edition, the right side routing from the panel to the front of the bell housing is in figure 38. The left side is clear in figure 42A.

You need access to a part manual. If you can't get to the online copy, get a printed one. If the owner is willing to spring for all those parts, he should be willing to buy the parts catalog.

 

[Charlie M]

Other thing I have run into it can be hard to find quality 6 volt parts, especially 6V regulators.12 volts sure does a crazy job of cranking those small motors.

 

[RTR]

(quoted from post at 22:41:50 04/06/16) I skimmed through the manual you posted, it looks like the paper copy I have. Neither provide a picture of how the wiring was routed. I tried, but failed to get anything off of the International website.

I'm sticking with 12v for the season, and replacing the s!@$ wiring that was spliced in. I'd still like to see how the wiring is supposed to look so I can get the battery back where it belongs. Owner is willing to pay for proper battery, wires, etc.

Positive battery cable routed from battery post out the front right of the box at top corner through a wire "hook" at gas tank bolt on the side (behind hydraulic lines) and then down to the starter.

Negative battery cable I believe was a flat braided ground strap and was fastened to either the upper battery box bolts (back of dash) or to the lower dash panel bolts.

 

[RTR]

(quoted from post at 00:33:33 04/07/16)

(quoted from post at 22:41:50 04/06/16) I skimmed through the manual you posted, it looks like the paper copy I have. Neither provide a picture of how the wiring was routed. I tried, but failed to get anything off of the International website.

I'm sticking with 12v for the season, and replacing the s!@$ wiring that was spliced in. I'd still like to see how the wiring is supposed to look so I can get the battery back where it belongs. Owner is willing to pay for proper battery, wires, etc.

Positive battery cable routed from battery post out the front right of the box at top corner through a wire "hook" at gas tank bolt on the side (behind hydraulic lines) and then down to the starter.

Negative battery cable I believe was a flat braided ground strap and was fastened to either the upper battery box bolts (back of dash) or to the lower dash panel bolts.

Use nothing but 00 gauge cables with the 6 volt system.

 

[worm12ga]

(quoted from post at 11:45:49 04/06/16)

(quoted from post at 12:41:50 04/06/16) I skimmed through the manual you posted, it looks like the paper copy I have. Neither provide a picture of how the wiring was routed. I tried, but failed to get anything off of the International website.

You need to look closer. In this edition, the right side routing from the panel to the front of the bell housing is in figure 38. The left side is clear in figure 42A.

You need access to a part manual. If you can't get to the online copy, get a printed one. If the owner is willing to spring for all those parts, he should be willing to buy the parts catalog.

I do have the parts manual, printed, as well, but I suspect it is missing some pages. I primarily need a view of the instrument panel from the battery side. I will review it again, and order a new one if i can't find what I need. I do have his credit card info :wink:

 

[David G]

NOTE:::::::::

The positive ground can destroy the alternator, post picture here before connecting a battery.

 

[worm12ga]

(quoted from post at 13:20:45 04/06/16) NOTE:::::::::

The positive ground can destroy the alternator, post picture here before connecting a battery.

It is negative grounded, with an alternator. No need for pictures, but I'll probably take some just to show the hack wiring job that was done to this poor machine.

How would it destroy the alternator (I'm genuinely curious)? I just assumed it simply wouldn't start if hooked up backwards.

 

[David G]

The alternator has diodes in it to rectify the alternating (AC) current to direct (DC) current, it is a dead short through them if polarity is reversed. You will get a lot of conflicting and incomplete information on the posts, I have been guilty of doing it, so you have to review them carefully.

 

[RTR]

(quoted from post at 00:33:33 04/07/16)

(quoted from post at 22:41:50 04/06/16) I skimmed through the manual you posted, it looks like the paper copy I have. Neither provide a picture of how the wiring was routed. I tried, but failed to get anything off of the International website.

I'm sticking with 12v for the season, and replacing the s!@$ wiring that was spliced in. I'd still like to see how the wiring is supposed to look so I can get the battery back where it belongs. Owner is willing to pay for proper battery, wires, etc.

Positive battery cable routed from battery post out the front right of the box at top corner through a wire "hook" at gas tank bolt on the side (behind hydraulic lines) and then down to the starter.

Negative battery cable I believe was a flat braided ground strap and was fastened to either the upper battery box bolts (back of dash) or to the lower dash panel bolts.

I should have also added that the original system was positive ground.

 

[worm12ga]

"I should have also added that the original system was positive ground."

I think that should have been obvious, but thank you for pointing it out anyway.

 

[John M]

Why is irrelevant now. Theres many reason to go with 12 volt, but from your description(s), it was a hack job, to fix a hack job. Regardless of where the factory ran the wires, the important thing to remember is to keep them out of the way of moving parts, to reduce the risk of them getting caught up in moving parts and away from the exhaust manifold. Some type of wire loom will help keep it neat looking, and protected.

 

[worm12ga]

Update: While trying to troubleshoot the wiring, I think I toasted the 12v starter. It's at the starter shop, along with the original 6v starter. They said they will call me with prices on a rebuilt 6v generator, and then I can decide which route to choose. Either way, this ain't gonna be cheap.

I think the starter died from crap splices, and a crap ground, dropping the voltage. The thing was hot to the touch after only a few ~7 second starting cycles (with maybe 30 seconds to cool in between).

 

[worm12ga]

When I pulled the starter switch, there was some pretty bad damage from arcing. It definitely had been going on for some time, I just had to have the bad luck to be the person it finally quit on.

 

[worm12ga]

Another update:

A bolt on the starter shaft had sheared off, and apparently stopped the 12v starter from working. The starter shop (which came highly recommended locally) replaced the ground up gear on the 6v starter, and said I could run it at 12v without problem. Tried to start, got maybe 2 'hits' and the starter just spun without turning the engine. Tried it 2 more times, with the same result. Pulled the starter, and there is a bolt loose in the nose, I can't tell if it's sheared off yet.