Ford 9N Ignition Issues

Ted

Ted

The pilot formerly known as Twin Engine Ted
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I have a 1930-something Ford 9N that my wife bought me for an anniversary present a few years ago. It ran and started great, the problem being that it had a rod knock. Well, actually all 4 rods knocking. So into the garage the thing went, engine pulled off, got it rebuilt. This has been a tremendously slow project, and really if I was smart I would've let someone else tackle it and gotten a different tractor. But, we like this thing - it really is cool. Tractor sat for about 2 years over the course of the engine rebuild due to me having too many irons in the fire.

The engine is rebuilt and back together, compression on all 4 cylinders. I wired up the tractor the way it was wired up, at least to the best of my recollection and from what I could tell. The thing has about 5 wires anyway. It's got a front mount distributor with electronic ignition installed, which was how I received it from the previous owner. It has had a 12V negative ground conversion, and the distributor only bolts to the engine one way so timing doesn't seem to be an issue.

The tractor has refused to start with the engine back together. It would catch and then immediately die after catching. It sounded like it has compression on all 4 cylinders. I've confirmed the firing order is correct and I confirmed spark at all 4 cylinders. So, my first thought was the carb that had been sitting for 2 years (and was an unknown age anyway) got gummed up. Got a replacement in, installed that, adjusted it, same problem. However then it got to where it wouldn't even catch after a bit, so I start looking at the distributor and see the coil is cracked and melted. I had left the key in the "on" position some during figuring things out with the engine not running, so it's possible that had caused the issue.

This got me questioning whether I wired the distributor correctly. The 9N distributor coil has one attachment on top and then it looks like it has another wire attachment on the side. It looks as though the side was never used. From the attachment to the coil on top, the electronic ignition module has one (red) wire that goes to it.

These tractors had a ballast resistor on them (which I haven't found on it yet). Supposedly even with the 12V negative ground conversions, you need to keep that ballast resistor. So it looks like the previous owner had screwed that up, which isn't surprising at all.

At this point I'm trying to figure out a few things:

1) What I should do for ignition components to replace. My options are to keep it as electronic ignition (just get new cap/rotor/module itself/coil), upgrade to the Pertronix automotive style coil, revert to points, or try to find a magneto to put on (which was another option). The magneto seems to be hard to find, so that's probably not a good option.

2) I'm also thinking about if I should be checking the cam timing to make sure that I haven't screwed things up there. The fact that the ignition mysteriously died after sitting for 2 years seems less probable, but I suppose it's possible since I don't know how old it was.

Ultimately I'm either used to magnetos and aircraft fuel systems or else modern fuel injection/electronic ignition/whatever from the factory.
 
Could it be the ignition switch? I know it's rare for switches to fail, but maybe the switch works in the "start" position, but not "run?"

You could simply bypass the switch to test.
 
KRyan said:
Could it be the ignition switch? I know it's rare for switches to fail, but maybe the switch works in the "start" position, but not "run?"

You could simply bypass the switch to test.
Click to expand...

I had thought that as well. It seems to still work in the run position, but it could be intermittently so such that when I release the key it fails. Easy enough to hook up a switch to test.
 
However I still need to buy new ignition components of some sort at this point.
 
I put a Petronix kit on my TO-30 years ago and it worked very well.
 
I've used the Pertronix coil and distributor/electronic ignition on the 351w in my boat and it works well. You don't want to use the ballast resistor with it though. I know you said you verified the firing order, but is it arranged properly on the distributor for the direction of rotation? I'm not familiar with the setup on the 8/9N, but verify the direction of the distributor rotor to make sure it isn't wired 180 out which could end up with a couple of cylinders correct, but not enough to get it to fire off and keep running. If that isn't clear, I'm saying you may have the firing order correct, but in a CCW direction when the dizzy spins CW, or vice versa.
 
So, you have determined that you ain't got spark?
The distributor isn't timed 1 crank rev off (1/2 cam rev)? (in general a common problem - you fire the plugs at the top of the exhaust stroke instead of compression)
 
You said it already has an electronic ignition setup (i.e. no points) so replacing it with a pertronix unit won't solve anything unless the electronic unit you have is already bad (not very common). If you are getting spark then the system is working. As far as wiring the distributor and coil, you should have +12v coming off of the keyed switch and running directly to the + side of the coil. Coming out of the distributor you should have two wires for the electronic ignition. One goes to the + side of the coil and the other goes to the - side. The coil fires when the - lead is connected to ground. I recommend getting a regular coil and not a high voltage coil for the tractor if you are planning on replacing it. I got one from napa for around $30. They use the same coil as the ford cars from the 50's to late 60's. Tractor supply also carries the coils in most stores if you have one near you.

I had similar problems with my 63 Ford 4000. It was always very hard to start. I had to clean the points every time I went to start it. I put in a pertronix unit thinking that would fix the problem. It didn't. What it turned out to be was actually the starter. The brushes in the starter were worn to the point where the starter was drawing so much amperage from the battery that the coil wasn't fully charging causing a weak spark. Rebuilding the starter was a simple job and should be the same process on the 9n. There are lots of youtube video's out there that walk you through it with no special tools needed if that ends up being your problem. Mine now fires up on less than a half a rotation.

If you aren't a member, yesterdaystractors.com is a great site for info and has a forum dedicated to 8 and 9n's.

Keith
 
Almost forgot, you didn't loose the spring clip when putting the distributor rotor back on did you? See the link below for what I am talking about. Without that little clip your rotor can rock back and forth a bit throwing the timing off. It is very easy to loose or forget to install it when putting the rotor back on (ask me how I know).

https://www.amazon.com/Rotor-Clip-N...coding=UTF8&psc=1&refRID=9RFAT3H918PY6G63TDJY

Keith
 
Sounds like classic ballast resister gone to me.



Edit: I photograph stuff before I take it apart now, makes reassembly much easier.
 
It really sounds like a missing or failed ballast resistor. Ted says he can't find it, which might be the problem. The starting circuit bypasses the resistor, giving full voltage to the coil for starting, and releasing the starter makes the ballast resistor carry the coil current. The idea with the setup was to use a coil designed for 8 volts or so, since the battery voltage drops a lot with the huge starter draw, and the ballast resistor drops the normal running voltage (13 to 14 volts or so) to the 8-volt level for the coil. A missing/failed resistor will let the coil fire during cranking, but not once the starter is released.
 
KRyan said:
Could it be the ignition switch? I know it's rare for switches to fail, but maybe the switch works in the "start" position, but not "run?"

You could simply bypass the switch to test.
Click to expand...
Pre-electronic ignition, one would find a resistor limiting current to the ignition coil when the switch was in the run position. The start position bypassed the resistor to ensure that you still got a spark when the voltage dropped as you cranked. If that still exists, it's a place to start. Also, ignition timing would be a good thing to check. My current tractor is an ancient 2017 Mahindra with electronic common-rail injection, though I think an old Ford would be a nice piece to have.
 
Dan Thomas said:
It really sounds like a missing or failed ballast resistor. Ted says he can't find it, which might be the problem. The starting circuit bypasses the resistor, giving full voltage to the coil for starting, and releasing the starter makes the ballast resistor carry the coil current. The idea with the setup was to use a coil designed for 8 volts or so, since the battery voltage drops a lot with the huge starter draw, and the ballast resistor drops the normal running voltage (13 to 14 volts or so) to the 8-volt level for the coil. A missing/failed resistor will let the coil fire during cranking, but not once the starter is released.
Click to expand...

Now THAT makes sense.

Ok, thanks. Now I've got a few things to look at on the tractor. Confirm timing/rotation/etc., confirm presence and function of the ballast resistor.

Oh, and order new parts. I'm trying to figure out whether I would've fried the electronic ignition module or not and if I need to replace that.
 
Tom-D said:
put it back to original, you can buy all the parts "NEW" and dump the 12v system they all were 6 volts from the factory, no ballast requiredhttps://www.tractorpartsasap.com/parts-categories/tractor-parts/ford-tractor-parts/9n.html?gclid=EAIaIQobChMIrpPj4Pyd4QIV7R-tBh0BBQKoEAAYAiAAEgKwn_D_BwE
Click to expand...

Tom, my understanding was the 6V systems had the ballast resistor as well and the 12V conversions were designed to be able to use the same ballast resistor that it came with new.

I could put it back to points, but honestly have little interest in doing that.
 
Ted DuPuis said:
Tom, my understanding was the 6V systems had the ballast resistor as well and the 12V conversions were designed to be able to use the same ballast resistor that it came with new.

I could put it back to points, but honestly have little interest in doing that.
Click to expand...
Which conversion kit do you have? do you run a 6 volt or a 12 volt battery?
 
Tom-D said:
Which conversion kit do you have? do you run a 6 volt or a 12 volt battery?
Click to expand...

I have no idea what conversion I have. It's a 12V battery, front mount distributor with the coil mounted on the distributor and an electronic ignition thingy located inside the distributor.

Tom-D said:
We used this on on my BIL's tractor, His was a 8N (1948 he bought new)

https://www.agkits.com/ford-120-2n-...V7yCtBh1iqQrVEAQYASABEgJHJvD_BwE#.XJkm-C2ZOWx
Click to expand...

That's more or less what I'm trying to decide - order something like that with the external/automotive coil or whether I should just get the parts to replace it as I have it now.
 
Minor correction to one of the comments above, the coil starts building energy when then - side is connected to ground, and it fires when that primary current is interrupted by disconnecting the - side from ground. Also, the condenser capacitor is not just about reducing RF noise in this configuration, it also helps tune the circuit, and helps provide a longer, hotter spark.
 
Ted DuPuis said:
12V conversions were designed
Click to expand...
FYI: there are 2 different EI kits for the N series front distributor: 1 used the same square coil and 1 replaced the square coil with a round coil, modified the distributor, and relocated the new coil. There are some after market 12v square coils out there but their internal resistance varies from 1.5 ohms to 4 ohms. In a true 12v systems no ballast is required to the coil. If you want to keep the front coil, measure the internal resistance of the replacement coil and ballast accordingly to the EI system requirement. I converted both my 8Ns to EI, but DIY'd the distributor mod by gutting an old square coil body, and bought NAPA coils.

A couple other bits: leaving the ignition on with EI will smoke the system unless you have a newer Petronix system which switches off primary voltage with no distributor rotation. On your initial start problem, those old style updraft carbs can be a pain to "prime." Even mine if they sit the summer I have to choke with my hand on the carb intake side, sometimes flooding it. Also if you haven't checked it, the fuel shutoff/sediment bowl assy has 2 screens in it. If it is the original good chance its clogged. Only option is replacement. And yes, sometimes the ignition switch can fail causing a substantial voltage drop. Once you figure out your current issues, prior to start, check spark at all plugs>check for positive fuel fuel at carb>if don't pop on initial try full choke with hand at carb. Good luck.
 
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Turn engine over until #1 is at TDC on the compression stroke (feel for compression with your thumb in the spark plug hole). Then look at rotor and see if it points to the #1 wire. If you can see the valves from the plug hole (small inspection mirror may help) the cam timing can be approximately checked by rotating engine to the other TDC (top of exhaust stroke). EX valve should close just before TDC, and IN valve open just after TDC.
 
Dan Thomas said:
It really sounds like a missing or failed ballast resistor.
Click to expand...

Ha, I remember those! The mid-70's Mopars we had when I was in highschool blew them so often Dad had a spare in each vehicle's glove box, along with a T-handle to remove the bolt and slap it back on.

HP-56129-5.jpg
 
Thanks additional good info.

One thing I'll say is I've never had problems with updraft carbs priming. But, leaving the ignition on makes sense for potentially frying it. Given that it was running beforehand, it's possible the ignition itself was fine and I ended up frying it that way. In which case, another question would be whether I fried the electronic ignition module this way as well or just the coil.
 
Here is the test for the coil. disconnect both wires using a pair of jumper wires connect one lead to the positive post of the battery, connect the other end of that lead to the positive post of the coil, then with a second jumper connect it to the negative post of the battery. place a coil wire to the coil's main lead, position it so it can make a spark jump to the block..
then make and break the connection to the negative lead of the coil. a spark should jump each time the connection is broken.
the little black unit in the distributor is the electronic unit for the electronic ignition, it amounts to a reluctor and a transistor to test it, all you need to do is excite the reluctor unit, by placing any iron by it, when it senses the iron's magnetic field, it will fire the coil, by opening negative lead to the coil.
So, the circuit is.... positive lead of the battery, to the electronic unit, electronic unit to the positive post of the coil. Negative post of the coil to any good ground.
 
-KLB- said:
Minor correction to one of the comments above, the coil starts building energy when then - side is connected to ground, and it fires when that primary current is interrupted by disconnecting the - side from ground. Also, the condenser capacitor is not just about reducing RF noise in this configuration, it also helps tune the circuit, and helps provide a longer, hotter spark.
Click to expand...
In most systems using points and condenser, a missing or open condenser will result in no spark at all. That condenser absorbs the electron flow when the points initially open, both to stop arcing at the points and to get the precipitous flux collapse in the coil that gets the secondary producing the spark. Without the condenser the points will arc, representing continued and slowly diminishing current flow at a time we need an abrupt cut to that flow.

Remove the condenser and see if the engine will run. It won't. That goes for battery ignition as well as magnetos.
 
The ballast resistor is behind the dash. Unless it’s been modified, it isn’t bypassed during start. It allows full current for start, then once running, decreases voltage to the coil. If it’s OEM, it probably didn’t fail.
The ignition switch is a common source of failure. I just bypassed mine this week until I can go get a new one. It was running fine, then just died while blading my drive. Meter shower I was getting 3V across it. I bypassed it and it started right up.
I don’t know EI, but leaving the key on can ruin the points if they shut down closed. The odds favor no damage though, cause I’ve left mine on a dozen times on the same set of points without any problem.
BTW, in my dealings w/these old Ns, EI seems to cause the most problems. I’ve had 3 with points, and have kept them all running fine. There’s a N forum with guys that know them inside and out. They’ll get it running for you if you can’t figure it out. 1st thing they’ll likely ask is to make sure you have the right coil for a 12v conversion.
 
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Dan Thomas said:
In most systems using points and condenser, a missing or open condenser will result in no spark at all. That condenser absorbs the electron flow when the points initially open, both to stop arcing at the points and to get the precipitous flux collapse in the coil that gets the secondary producing the spark. Without the condenser the points will arc, representing continued and slowly diminishing current flow at a time we need an abrupt cut to that flow.

Remove the condenser and see if the engine will run. It won't. That goes for battery ignition as well as magnetos.
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Big note:
he already has electronic ignition and no points or condenser.
 
Does it have the original key.??

Or has it been replaced with a screw driver.??

As I read this I was thinking ballast resistor or ignition switch.

But you know me, why go stock when you can be different.???

 
I have some time logged on one of those.
 
You dont need the balast resistor if using a 12v coil and electronic ignition If you think the coil is bad replace it with a napa ech ic14 coil and make sure it is wired like I said in an earlier post.

Keith
 
The Pertronix module is nothing but a 4prong GM ignition module from the 80's. You can get one for like $5 from RockAuto. Wires to 12v battery, ground, coil and reluctor in distributor, no ballast resistor required. Just make sure it has a good heat sink, them sucka's get hot.
 
Zeldman said:
Does it have the original key.??

Or has it been replaced with a screw driver.??

As I read this I was thinking ballast resistor or ignition switch.

But you know me, why go stock when you can be different.???

Click to expand...

When we decided to do the engine rebuild I actually really wanted to do the flathead V8 conversion. I couldn't convince Laurie on the idea - she wanted to keep the 4-cylinder figuring this was a good "first tractor" for the kids to drive, and 100 HP would probably screw that up. That said, once I get this going part of me thinks another 2/8/9N with a V8 and turf tires would make a good option for mowing the runway without getting big ruts in it once we have that done. Another idea for another day.

I did take a look and confirmed there is no ballast resistor in the 9N currently. I'm getting a lot of differing opinions above as to whether or not the thing is needed with the 12V conversion and the distributor-mounted coil, so not quite sure what I need to order here or not, and how it would need to get wired. The ignition switch may very well be a problem. I did notice arcing at one point with it in the on position and the lead wire disconnected, but that doesn't mean that there isn't a significant amount of resistance within the switch, so I should check that and then I can look at bypassing some things.

Now, I still have to figure out what to order. Coil (it's melted, it's dead), cap/rotor, still not sure about the electric ignition module. Actually Tractor Supply has the parts, so I could just buy them there are not order anything.
 
Well, if there is no ballast resistor, then the ignition circuit is probably fine. If your 12V ignition is supposed to use a ballast resistor (doubtful) then your tractor would still start/run, it would just burn it up quicker seeing all 12V instead of the reduction via ballast resistor. I'd just get a new coil and see where you get.
 
You should trouble shoot with a volt ohmmeter before buying anything. Start with the switch and work through the system. Find a wiring diagram for the electronic ignition and figure out if you need a ballast resistor. Check all interlocks. Buying parts willy nilly might never fix this.
 
SoonerAviator said:
Well, if there is no ballast resistor, then the ignition circuit is probably fine. If your 12V ignition is supposed to use a ballast resistor (doubtful) then your tractor would still start/run, it would just burn it up quicker seeing all 12V instead of the reduction via ballast resistor. I'd just get a new coil and see where you get.
Click to expand...
Normally when these tractors are converted to electronic ignition, and 12 volts the battery, coil and starter will be changed to a 12 volt version, and the points removed and the electronic version installed.
 
Tom-D said:
Normally when these tractors are converted to electronic ignition, and 12 volts the battery, coil and starter will be changed to a 12 volt version, and the points removed and the electronic version installed.
Click to expand...

Agreed. That's why I mentioned it was doubtful that the electronic ignition required a ballast resistor to be present because they generally need 12V to operate. I bypassed the ballast resistor on my boat when installing the Pertronix unit, although it was a 12V system already, not a 6V conversion.
 
Keep in mind the coil has physically melted. As in it's cracked and goo started coming out of it. It needs to be replaced. The cap also is worn and so is the rotor. So all of that stuff is logical step 1 replacement items.
 
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