I'm an idiot...connected jumper cables backwards

TimP · Nov 28, 2021

So, I just bought a small farm in South Central MO and a Ford 9N came with it. I saw the previous owner start the tractor this past April via video and it started right up. I moved this past October from NH to the property in MO and finally got around to trying to start the tractor.

It wasn't until the battery went dead that I realized he had turned off the gas petcock so there was no gas getting to the carb. BTW, this has had the 12v conversion done to it.

Fast forward a few days later...I tried to jump it and nothing...it wouldn't turn over. It wasn't until I smelled someting hot that I realized that the RED wire off the battery went to ground (positive ground?). That's where I attached the red jumper cable. I swapped the cables ends and now the starter turns but it won't start..

I noticed that the part that I smelled was near the ammeter. I don't know if I cooked this or not.

Since that time, I haven't had a chance to look into what I may have done. I'm hoping this week I will have a chance to get back to the tractor and get it running or at least troubleshoot it.

It's a pretty simple system but I was hoping someone who knows this electrical system cold might point me in the general direction as to where to start to look.

The first thing I'm going to check, of course is to see if I have spark.

I grew up on a farm with my dad having several Farmalls but that was 50+ years ago. I know my way around engines so I'm hoping this won't be a big deal.

I'll let you all know how I make out...

This post was edited by TimP on 11/28/2021 at 09:25 pm.

Jim.ME · Nov 29, 2021

First thing. Just because a wire or cable is red, does not make it positive, there is no rule or law red is only positive. Red, black, blue; battery cables are available in many colors and will fit on either battery post. In the case of a battery cable, you need to look at the battery and see which battery terminal the red cable is hooked to. DO NOT go by cable color.

If the 12-volt conversion has an alternator there is the possibility the alternator was damaged as well, as alternators are polarity sensitive.

Bruce (VA) · Nov 29, 2021

If it has EI, that too is likely fried. Points will be fine.
75 Tips

TimP · Nov 29, 2021

Yeah, Thanks, I should know this too...being an electronics tech for over 45 years, I have mostly learned that one should never assume...[u:1289944885]mostly[/u:1289944885] . I saw the red battery wire and didn't follow it to see where it went...when I saw (finally) that it went ground, that's when my heart sank and I was privately embarrassed .

I'll be checking things out today. It's supposed to be relatively warm today here.

TimP · Nov 29, 2021

Thanks...I was going to check for that today. I don't think it does but I'm not 100% sure yet.

Hobo,NC · Nov 29, 2021

I hauled a 9N in yesterday 12V with alt and EI. He put the battery in backwards I farmerized the battery cables got the bat in right it fired up and drove on the trailer.

The alt wires are toasted and I think the alt charges how good I don't know...

TimP · Nov 29, 2021

(quoted from post at 08:47:20 11/29/21)
I hauled a 9N in yesterday 12V with alt and EI. He put the battery in backwards I farmerized the battery cables got the bat in right it fired up and drove on the trailer.

The alt wires are toasted and I think the alt charges how good I don't know...

This is encouraging...we shall see, hopefully today.

old · Nov 29, 2021

South central MO as in where?? I'm here at the Lake of the Ozarks

TimP · Nov 29, 2021

(quoted from post at 10:56:57 11/29/21) South central MO as in where?? I'm here at the Lake of the Ozarks

Just south of Mt. View, north of West Plains.

DennyD · Nov 29, 2021

AS a person works on these tractors, the beauty of fuses and/or fusible links starts to reveal itself amid rewiring/upgrades. But like a lot of folks, my own 8N is deficient regarding that kind of protection.

hunkydory · Nov 29, 2021

(quoted from post at 15:23:38 11/29/21) AS a person works on these tractors, the beauty of fuses and/or fusible links starts to reveal itself amid rewiring/upgrades. But like a lot of folks, my own 8N is deficient regarding that kind of protection.

Amen.

As I go through mine it's a constant battle of function over form. Function usually wins.

Eman85 · Nov 29, 2021

I'm confused. Is the red wire/battery cable attached at the positive post of the battery? If it is and the tractor is wired as positive ground then hooking up a jumper with the positive to positive shouldn't have caused a problem unless you had the bumpers touching.

ASEguy · Dec 1, 2021

Is the red wire you mentioned going to the small post or the large one on the battery? Go by post size and not wire color.

TimP · Dec 1, 2021

(quoted from post at 21:27:39 11/29/21)
I'm confused. Is the red wire/battery cable attached at the positive post of the battery? If it is and the tractor is wired as positive ground then hooking up a jumper with the positive to positive shouldn't have caused a problem unless you had the bumpers touching.

Sorry for the delay in answering...I've been away for a few days.

I looked at the tractor today...

The negative post (which has the RED wire connected to it) goes to ground. The positive terminal goes to the wiring harness.

Sorry for the confusion. I saw RED and thought positive. I thought I read somewhere that the 9N was positive ground and that's what I was thinking. When it was converted to 12V, maybe the tractor became negative ground?

I have manuals for this tractor but they are packed away. I'm looking for them today.

I'm also going to put a charger on the battery today so I don't need to try and jump start the tractor. Some newer vehicles don't appreciate being the "donor". I have a 2010 Tacoma

This post was edited by TimP on 12/01/2021 at 08:50 am.

TheOldHokie · Dec 1, 2021

(quoted from post at 12:46:05 12/01/21)

(quoted from post at 21:27:39 11/29/21)
I'm confused. Is the red wire/battery cable attached at the positive post of the battery? If it is and the tractor is wired as positive ground then hooking up a jumper with the positive to positive shouldn't have caused a problem unless you had the bumpers touching.

Click to expand...

Sorry for the delay in answering...I've been away for a few days.

I looked at the tractor today...

The negative post (which has the RED wire connected to it) goes to ground. The positive terminal goes to the wiring harness.

Sorry for the confusion. I saw RED and thought positive. I thought I read somewhere that the 9N was positive ground and that's what I was thinking. When it was converted to 12V, maybe the tractor became negative ground?

I have manuals for this tractor but they are packed away. I'm looking for them today.

I'm also going to put a charger on the battery today so I don't need to try and jump start the tractor. Some newer vehicles don't appreciate being the "donor". I have a 2010 Tacoma

This post was edited by TimP on 12/01/2021 at 08:50 am.

Sounds like the PO simply put a 12v battery in it and switched the terminals going to the original wires. That would match post size and the alternator but not wire color. Makes perfect sense in a strange way.

TOH

TimP · Dec 1, 2021

(quoted from post at 12:56:04 12/01/21)

(quoted from post at 12:46:05 12/01/21)

(quoted from post at 21:27:39 11/29/21)
I'm confused. Is the red wire/battery cable attached at the positive post of the battery? If it is and the tractor is wired as positive ground then hooking up a jumper with the positive to positive shouldn't have caused a problem unless you had the bumpers touching.

Click to expand...

Sorry for the delay in answering...I've been away for a few days.

I looked at the tractor today...

The negative post (which has the RED wire connected to it) goes to ground. The positive terminal goes to the wiring harness.

Sorry for the confusion. I saw RED and thought positive. I thought I read somewhere that the 9N was positive ground and that's what I was thinking. When it was converted to 12V, maybe the tractor became negative ground?

I have manuals for this tractor but they are packed away. I'm looking for them today.

I'm also going to put a charger on the battery today so I don't need to try and jump start the tractor. Some newer vehicles don't appreciate being the "donor". I have a 2010 Tacoma

This post was edited by TimP on 12/01/2021 at 08:50 am.

Click to expand...

Sounds like the PO simply put a 12v battery in it and switched the terminals going to the original wires. That would match post size and the alternator but not wire color. Makes perfect sense in a strange way.

TOH

Yes, that's what I think too. Battery is very dead (1.2V) so I doubt it would even respond to a charger. I am heading out to buy a new battery and two new battery post terminals. The terminal and posts were very beat up.

TimP · Dec 1, 2021

I bought a new battery and post clamps...with the battery reading about 1.2ish volts at the terminals with clamps removed I knew there was no bringing that battery back from the dead.

The post clamps were pretty gnarly too so those will be replaced as well.

We'll see what happens tomorrow.

It's supposed to be nice with temps in the mid to high 70's so it'll be pleasant weather to work on it...

This post was edited by TimP on 12/01/2021 at 06:21 pm.

TimP · Dec 2, 2021

OK, new battery installed and after reseating the spark plug wires, it grudgingly started.

After it warmed up a little, the engine evened out and it just purred.

I heard squeaking in the front and found that the alternator belt was rubbing on the lower front of the engine. I think that the belt is too short so I can't swing the alternator far enough down on the lower mounting bolt so the belt can clear that part of the engine.

There's a lot about this tractor that I don't know about. It seems the 3 point lift doesn't lift when I pull the lever up...My brother in law lives about 3 miles away and he's quite familiar with tractors...he has three.

He'll be over in the next couple of days to look it over with me...

BTW, this is where it's rubbing (not my tractor but this is a good picture of the area).

I need to order or fabricate a top mounting bracket it seems. The previous owner just kludged something there but it doesn't work.

This post was edited by TimP on 12/02/2021 at 10:57 am.

CKain(MI) · Dec 2, 2021

I am late in reading this post. BUT, number one-- 99% of the time a conversion is done, 6 volt to 12 volt, the alternator is
a 12v negative ground.... No 2, From then on the battery is wired 'black to chassis'(neg grnd), 'red to starter solenoid' or
starter. As another replied here, alternators are polarity sensitive and will be damaged if wired in reverse. A generator
could be 'polarized' either way. The alternator has a rectifier inside that doesn't allow that and they usually are stamped in the frame, NEG...

TimP · Dec 2, 2021

(quoted from post at 20:34:12 12/02/21) I am late in reading this post. BUT, number one-- 99% of the time a conversion is done, 6 volt to 12 volt, the alternator is
a 12v negative ground.... No 2, From then on the battery is wired 'black to chassis'(neg grnd), 'red to starter solenoid' or
starter. As another replied here, alternators are polarity sensitive and will be damaged if wired in reverse. A generator
could be 'polarized' either way. The alternator has a rectifier inside that doesn't allow that and they usually are stamped in the frame, NEG...

I'm good to go in that regard...Negative terminal on battery goes to chassis. I verified that the battery is indeed charging.

I need to suss out the alternator bracket assy. I think that the PO kludged a "bracket" of sorts and it didn't work. I also think that the belt he chose to use is too small in diameter, causing the belt to rub in the area under the front distributor (Explained in previous post).

With the belt that's in there now, I can't pull the alternator far away enough from the engine for the belt to clear that area in the big circle. That tells me that the belt is too short....or routed incorrectly. I ran into this issue as it was getting dark outside so I had to let it go until tomorrow.

This post was edited by TimP on 12/02/2021 at 06:49 pm.

Mad Farmer · Dec 3, 2021

(quoted from post at 19:44:31 12/02/21)

(quoted from post at 20:34:12 12/02/21) I am late in reading this post. BUT, number one-- 99% of the time a conversion is done, 6 volt to 12 volt, the alternator is
a 12v negative ground.... No 2, From then on the battery is wired 'black to chassis'(neg grnd), 'red to starter solenoid' or
starter. As another replied here, alternators are polarity sensitive and will be damaged if wired in reverse. A generator
could be 'polarized' either way. The alternator has a rectifier inside that doesn't allow that and they usually are stamped in the frame, NEG...

Click to expand...

I'm good to go in that regard...Negative terminal on battery goes to chassis. I verified that the battery is indeed charging.

I need to suss out the alternator bracket assy. I think that the PO kludged a "bracket" of sorts and it didn't work. I also think that the belt he chose to use is too small in diameter, causing the belt to rub in the area under the front distributor (Explained in previous post).

With the belt that's in there now, I can't pull the alternator far away enough from the engine for the belt to clear that area in the big circle. That tells me that the belt is too short....or routed incorrectly. I ran into this issue as it was getting dark outside so I had to let it go until tomorrow.

This post was edited by TimP on 12/02/2021 at 06:49 pm.

Does the alternator have a pulley that takes the wider tractor belt?

Hobo,NC · Dec 3, 2021

Those brackets are the normal 12V conversion brackets that come in a kit. The bottom bracket will pivot down even then the belt is a close fit.

The one I just replaced the alt/belt on I used a B43 belt You hold the alt up not bolted on install the belt then the lower bolt in the alt. Yes its a tight fit...

On a new install you go find a ditch to check for the axle/alt interference. On all the axle will hit the alt are come close its best to go ahead and weld a 1/2" piece of plate to the lower part of the left axle support.

Its a tight fit some have added a idler pully to move it out sorry no pix. I remember soundguy posting a pix of his idler.

Hobo,NC · Dec 3, 2021

Your pully looks correct for a 5/8" belt no need to fudge with it.

Mad Farmer · Dec 3, 2021

(quoted from post at 06:08:09 12/03/21)
Your pully looks correct for a 5/8" belt no need to fudge with it.

That picture is not from his tractor........

Hobo,NC · Dec 3, 2021

Sham on him : (

TimP · Dec 3, 2021

(quoted from post at 10:05:59 12/03/21)

(quoted from post at 06:08:09 12/03/21)
Your pully looks correct for a 5/8" belt no need to fudge with it.

Click to expand...

That picture is not from his tractor........

Yeah, that picture was from one I found on line. I couldn't take a decent enough picture of my tractor..

On the same subject, most of the correct brackets I have found online, including here, require removing two head bolts. Is that going to be a big deal? I surmise they can be removed and then when reinstalling them just use a torque wrench to make sure they are installed with the correct amount of torque?

JMOR · Dec 3, 2021

Here ya go, Hobo.

Smokeonthewater · Dec 4, 2021

Those lower brackets are junk... crappy design....
If you look in my build thread "$1500" you can see where I modified that bracket for a MUCH better fit.

Smokeonthewater · Dec 4, 2021

TimP · Dec 4, 2021

(quoted from post at 22:37:29 12/04/21) Those lower brackets are junk... crappy design....
If you look in my build thread "$1500" you can see where I modified that bracket for a MUCH better fit.

I'll check it out...Thanks!

I'm an idiot...connected jumper cables backwards

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