International 444 - No Spark

Hi, having trouble with my 444 not starting and wondering if anyone here has any ideas.

It looks like I'm not getting any spark. Checked by taking one plug out, connecting to its wire and holding up against the block, and could not see any spark while cranking. Also got a spark tester at the auto parts store to make this more visible and still not showing that it's getting any spark.

I do have voltage at the coil (+) terminal (same as battery voltage, about 13.4V).

I haven't replaced the points or condenser because I don't have one on hand, but I did check the points gap: 0.024, spec is 0.020.

Sounds unlikely, but I did turn the engine over by hand with the dist cap off and made sure that the shaft is turning and the points are opening and closing.

Based on the above, I replaced the coil, but still no spark.I haven't been able to find the specs for the coil windings, but the old coil measured 1.1 ohms on the primary and 5500 on the secondary. The replacement coil measured 1.3 ohms on primary, 13,000 on secondary.

What the heck am I missing?

It seems like if the points are opening and closing and the coil has voltage at the (+), it should be generating spark.

Has anyone tested a coil directly by disconnecting the wire on the (-) terminal, then connecting a jumper from there to ground, then breaking the connection to ground to force the coil to generate a spark?

Thanks for any ideas.
Keith

What condition are your points in - are they burned or coated with a film? If they are burned they can be filed to a clean area and reused. Make sure you wipe off any film or filings on them and reset them.
Concerning the coil, sounds like you have a 12 coil which means internally its dropping down to 6 volts for the points. I know when a 6 v coil is used and requires an external resistor those do go bad over
time and you have no voltage. I don't know if that same thing can happen with a 12 v coil.

Hey, and if pigs had wings they could fly right?

Why are you so afraid to address the points?

Pull them, check the contacts, clean and gap them to within spec range.

There are a good handfull of reasons why they might function mechanically but not electrically.

Lets backup.

Reading voltage at the coil may be false hope. A wire as thick as a baby's hair will show voltage to the coil. But not carry ignition current. I have seen switch innards so coroded and primary coil wires broke and coroded in the insulation, but they conducted enough to register on a high impedance volt meter.

So first, clean and gap points.

Disconnect coil primary from distributor.

Use your ohm meter. One probe to ground, one probe to the contact on the distrib where the primary wire went. Set to continuity or low ohms setting. Have someone roll enging over. Should have continuity closed and nit open.

Can do this with a test lamp. Clip to bat, probe to contact, roll engine over, lamp should blink.

If it stays on when points are open you have a short. Prime suspects are condenser, points hinge insulator, any wiring from side of distrib to points, and the insulated points contact on the breaker plate.

If it never comes on check gap and contacts condition, and wiring from side of distrib to points.

Once you have that working, jump bat to coil, hook coil to distrib, and give a try. If it works, but dies when you remove the power bypass, you know wirining to/from key switch or switch itself is suspect.

Pull the coil wire out of the cap and use a cloths pin or? to hold it 1/4" away from the block. With it in neutral and brakes locked, take off the distributor cap and let it hang
on the remaining wires. turn on the key to run, and use a small screw driver to wiggle the point's movable arm. This wiggling should make and break the connection like the points
were opening and closing. Lifting and releasing the points is OK to do. If sparking happens at the coil wire, you have discovered a bad set of points, replace them and set to
.020". also pass a folded dollar or non fiber paper between the new points to clean preservative film off of them. Now try cranking and see if there is spark at the block. Jim

Wow, thank you! Now I've got somewhere to go. I think I will try to verify the coil first just with a jumper to ground. Then if that checks out, try JA's suggestion to check if opening the points fires the coil. If no good, I can track it down further with Soundguy's suggestions on checking the ground side.

Actually, I should probably go get points and a condenser at the dealer at lunch time just in case, so I don't get stuck this weekend if I need them.

JA, we're not so far apart, I'm in Monticello on the river.

Keith

Good point on the wire to the coil terminal, too, I hadn't thought of that. Some of the wiring is not in the best shape.

FWIW here's my Ignition Troubleshooting Procedure. Print it out take it to the shop and work through it one step at a time can find the problem.

http://www.ytmag.com/cgi-bin/viewit.cgi?bd=farmall&th=5745

John T
John Ts Ignition Test

Sweet! Thanks. Printed out and ready to go outside after work.

"Concerning the coil, sounds like you have a 12 coil which means internally its dropping down to 6 volts for the points."

You have been misinformed or have bad understanding, here.

I think 444s were all 12v. A 12v coil designed for use with an external resistor will be very close to the specs of a 6volt coil. They operate in a 6 volt environment. A true 12v coil runs at 14.2 or so volts and does not reduce the voltage internally. The points ground the side of the coil connected to the distributor terminal, and when they open there is 12 volts there. Not a flame!!! JIm

Where would the external resistor be? I didn't see any. The coil that was on it had "6V 12V with res" printed on it. I bought a new coil, going off the parts list what should have been the right coil on it - a 12V coil now.

Some progress... No spark direct from the coil to ground (small gap). Then connected a test light to the coil (-) terminal, cranked the engine and it stayed on constantly... points not closing... or open circuit between one side of the points and ground.

Need to get points and condenser tomorrow from the dealer. Also need to try a direct jumper to ground from the coil (-) terminal... break the contact and make sure the coil does fire.

On some newer IH the resistor is built into the wire from the key to the coil. When you ground the side of the coil going to the points tomorrow, also measure the voltage at the key side of the coil. If it still measures about 12v, there is no resistor. If it measures about 6 to 7 there is a resistor. It will read full 12v if the distributor side is not grounded, even though there is a resistor. It takes the "load" of the coil to actually drop the voltage. Both sides of the coil will read 12+ volts when the points are open and the wire is connected. Don't leave the ignition of for more than a minute or so or the coil can over heat. Jim

Youre getting there:

"Some progress... No spark direct from the coil to ground (small gap). Then connected a test light to the coil (-) terminal, cranked the engine and it stayed on constantly... points not closing... or open circuit between one side of the points and ground."

That's right, a test lamp on the coils to distributor/ground terminal as the engine is cranked over with IGN ON should flash ON (points open) and OFF (points closed). If it never goes off, points are NOT fully closing or badly burned or the wiring from coil to points is open or the distributor isn't getting a good ground.

John T

Making progress! Had it running briefly today... only briefly because I have a carb problem also, so after running for a minute or so I shut it down to take the carb off.

This is a good learning experience, if I am to take away the positive. I realized that I haven't had a vehicle with points since my Yamaha DT125 back in, ohhhhh... 1974?
So it's not second nature to me.

Got the new points and condenser in. What a pain! This really should be one of the easiest engines to work on, but with a 2050 loader on, there's a big wide frame right where I need to reach everything. I swear it took me an hour just to get the condenser in. Anyway, got those in finally and set the gap to 0.020. Checked the continuity to ground with points open and closed and it looked good. The old points were blackened, and a little bit of pitting. If I were to look at them without knowing what they came from, I would have thought they'd be okay. But, my previous testing had shown that they were not making contact, so apparently they were burnt enough to fail.

Then I turned back to the coil, which I hadn't yet been able to get any spark out of, even using a jumper wire direct from coil (-) to ground. Tried the original coil just for fun, no spark. Then remembered what Soundguy said about the wire to the high side of the coil being able to conduct enough current. So I put in a length of wire from the starter 'R' terminal to the coil '+'. NOW, I got spark!

The odd thing was that this was the old coil. So I switched back to the new coil, keeping the new jumper wire in, and still no spark on that one. Switch to old one, have spark. The new coil was what the dealer showed as the correct one for the C153 engine in the 444, and is a 12V coil. The old coil is "6V 12V with Res". When I measured the coil dist side terminal (-) with switch on and not grounded, I got battery voltage, no voltage drop, so that means no resistor in the circuit? And it's 12V electrics, not 6V to 12V conversion - built with 12V system as far as I know. Confused. But for the moment, not going to argue with success. It runs.

Just need to wire in the starter-to-coil jumper in a permanent way and get the carb sorted out.

Sorry for anyone reading these, I seem to be submitting replies in a mixed up order.

About the points. I was curious how they got burned. The initial failure on the tractor was the float valve in the carb getting stuck. The short length of hose on the intake side of the carb had come loose, and some grit must have gotten into for the float valve. Started sputtering and popping... by the time I got back by the garage there was gasoline dripping out of the carb.

Before this happened, of course, I was getting spark and the engine was running fine. But sometime after I parked it and while trying to get it restarted I lost spark.

So, as I understand it, when the points open, opening the primary circuit on the coil, voltage builds in the secondary until it's enough to jump the gap at the spark plug. If I was trying to start the engine when it was flooded, and there was a super-rich mixture in the cylinders, would it take a much higher voltage to ionize the gases in the spark plug gap? And would that higher voltage from the coil be enough to cause arcing at the points that wouldn't happen under normal conditions?

It runs! Hopefully my video links work.
444 running at idle

At high idle...

Seems to be running better than ever! Of course, it's a bit hard to tell since it's been down for 4 weeks, and one of the ex pipes was coming loose before, so it was LOUD. But I'm pretty sure it's running smoother.
444 High Idle