8N Problems - Please advise

Hello, I bought an 8N a few years ago, it ran for a year and then died. It sat for another year until I got the guts to work on it.

I went to the local tractor place and he sold me a coil. I replaced that and it ran for a few minutes and the coil burned out.

He then sold me the entire 12V conversion kit along with an ammeter and a key switch and said to replace all of that. I also replaced the spark plugs and the spark plug wires.

This is the wiring diagram he said to follow and he said if there was a junction box, not to use it. There was no junction box. Previously there was no resister either.

I wired it up, turned the key, pushed the starter and nothing happened except for a little smoke came out of the resister.

I looked up another wiring diagram and saw a second resister as well as more "stuff" going on around the alternator. Currently there is NOTHING going to the R Terminals - on my previous alternator there was what looked like a capacitor going to the R terminals.

Do I need to add a junction box and if so, where does it mount? Do I need something else at the alternator? The only parts that are not new in the diagram are the starter switch and the starter Selenoid... Should I replace both of those?

Should I re-replace the resister that I saw a little smoke coming out of or was it burning off some residue from the manufacturing process?

I would love to get this thing running... I am amazing myself that I have figured out as much as I have on this thing. Thanks for any and all leads. The battery is fully charged.

Rich

I figured that the resister was taking a smoke break or something. thanks for the chuckle.

Here is the wiring diagram I created after I converted my 48 8N (front mount) to 12 volts.

There are a couple of questions that I have from looking at your diagram. First, you need to know if your alternator is a 1 wire or a 3 wire. Mine is a 3 wire. Second, is your coil a 6 volt or 12 volt? Mine is a 6 volt.

Danny

Here's a link that I've found to be helpful. Hope you find something you can use. Also, Dell's advice has always been right on for me, so I'd listen carefully to what he says.

Link

HTH

Here's a link that I've found to be helpful. Hope you find something you can use. Also, Dell's advice has always been right on for me, so I'd listen carefully to what he says.

HTH

1st off) ignition coil. gotta know/make decision wheather to use the OEM 6 volt squarecan coil, or the modern 12 volt squarecan coil. Unfortunately, the coils are NOT MARKED except on the box. Since you've burned out one coil according to your diagram, that implys its an OEM 6 volt coil. The OEM 6 volt coil always REQUIRES the "infamous ballast resistor" mounted on the backside of the dashpanel under the ammeter. (doesn't matter, 6 or 12 volts, OEM 6 volt coil always requires the "infamous ballast resistor)

Then the OEM 6 volt squarecan coil ALSO requires a 12 to 6 volt converting resistor. p/n 8NE10306 is a 12 to 6 volt converting resistor. ...BUT... you still need that "infamous ballast resistor" connected in series like flashlight batterys. It can go between your ignition key and 12/6 resistor or it can go between 12/6 resistor and frontmount squarecan coil. Understand?

Oh year, new ceramic resistors ALWAYS SMOKE, don't worry, it'll disapear after about 30 minutes. You just saw it, cuz yer watching, and that is good.

Junction box? usually call it junction BLOCK. it holds the "infamous ballast resistor" under the ammeter. p/n 8N12250. Hook the battery supply wire to the center terminal, and one wire of the ignition switch. The other ignition switch wire then connects to one side of the "infamous ballast resistor". The other side of the ballast resistor would normally go thru the sparkie tube to the top terminal of the squarecan ignition coil. Somewhere in that wiring line-up between the ignition ON switch wire and the 6 volt coil has to be the 12-6 volt converting resistor. Mount it where it can't melt plastic wire insulation.

I'm gonna assume yer alternator is the popular common 3-terminal Delco 10-SI 12 volt alternator with built-in electronic voltage regulator. The common wiring scheme P-2 (remote sense) has short wire connected directly to the BIG BATT STUD at back of alterator. Then the P-1 (switched excite) "R" terminal? is connected thru a resistor to the ignition ON switch wire terminal block.

There is the possiblility that your "R" terminal name is for the P-2 "remote sense" terminal. In which case, connect "R" with short wire to BIG BATT STUD output. And connect P-1 (switched excite) thru yer extra resistor to the igniton switch ON terminal. Understand?

There are many ways to convert to 12 volts, some of 'em even work..... .....respectfully, Dell a 12 volt advocate for the right reasons

That said, I haven't found the right reason for my eazy starting 6 volt 52 8N. And I know 8-ways to do it right the first time.

One question regarding the "infamous ballast resistor"... I have since replaced the coil that burned out. It came with the 12v conversion kit so once again there is no telling if it is a 12v or a 6v coil. Will it hurt a 12v coil if the "IBR" is added? What symptoms would you expect if it does turn out to be a 12V coil?

Also, any thoughts on replacing the starter switch or starter selenoid?

Thanks for the leads... I may have more questions about the alternator after I go home and take a closer look at things.

Thanks,

Rich

Ignition switch and starter solenoid don't care, 6 or 12 volts. Starter motor don't care 6 or 12 volts, positive or negative ground ...BUT... 12 volt alternator DEMANDS NEGATIVE GROUND. Ammeter don't care, 6 or 12 volts, positive or negative ground ...BUT... yer eyeballs do care. You've been trained for (+) ammeter reading to indicate battery CHARGE, wheather positive or negative ground, (+) is CHARGE..... .....Dell

As to your starter problem.. So? when you hit the thumb button.. the starter doesn't turn?

Do you have the wire from the thumb button hooked to the small third terminal of the oem 3 terminal solenoid.. and is the third terminal still facing the tractor? ( needs to be like that, as the solenoid is internally hot.. and that third terminal is merely ground, via the tranny interlocked switch. To test the switch.. either use a VOM and look for continuity from the switch contact to ground when you hit the switch ( disconnected ), or simply ground the small wire and see if the starter spins over /.. make sure you are in neutral.

Also.. you may want to find another parts place to buy your stuff at.. this guy is just throwing parts mindlessly at you without telling you how to diagnose the problem in the first place.. then he sells you a whole new electrical system.. still with no help. In fact.. he's only helping his pocket get lined with your money.

He should have addressed your original problem of not starting. When the coil he sold you burned up.. that showed that you needed more/correct resistance in line with it.. and to verify some wireing.

In reality.. you at most probably needed a resistor block, a wire harness, and again.. a new coil.

He didn't do you any favors. Hopefully we can get this worked out for you.

Soundguy

I will test the starter switch tonight and check which terminal the wire from the starter switch is going to... off the top of my head, I think it is the terminal facing AWAY from the tractor, but I will double check that.

You mentioned verifying what coil I have rather than guessing. Is there a way I can do that?

Thanks.

There is no true/false straight cut test for a 6v vs 12v coil.. but if you have a decent VOM you can make an educated guess.

Measure the primary and secondary windings on the ohm scale... for a 6v front mount.. look for very low.. like 1.x ohms for the primary.. and about 4000 for the secondary. For the 12v coil.. look for something more like 2.x+ for the primary and 7000 on the secondary. See what I mean... primary ohm values are very dicey.. only a very acurate meter will help on that.. luckilly you can also compair the secondary values as well.

Soundguy

ALWAYS CHECK for ohmmeter "ZERO" before you measure any resistances by connecting the 2-testleads together. Iff'n fer example yer shorted leads read 1.2 ohms, then you would expect ALL LOW OHM readings to be +1.2 ohms too much. This makes for a MAJOR ERROR when reading low ohms like ignition coil primary resistances. Good ohmmeters have a "ZERO" adjust but modern ohmmeters generally ignore that technical nicety.

Simply measure from the top terminal to eather of the bottom terminals. The secondary winding (tab) will be about 7000 ohms (for both) and the primary winding (springy-thingy) will be about 1 ohm for a OEM 6 volt and 3 ohm for a 12 volt coil.

I always urge replacement squarecan frontcoils to be permanently externally marked as for 6 or 12 volts. That way, there is no question 10 years from now..... ..... Dell

Previously there was no resistor but I have seen a few different diagrams - some call for one resistor, others call for two. I was hoping the tractor might at least try to turn over but no luck so far.

Where in Michigan do you live?