1941 ford 9n no spark

Changed to a twelve-volt from 6-volt -starter went bad-changed it-put in new points-condenser etc. New plug wires. New starter switch,NO SPARK By the way,after changing to twelve volt she ran great for a long time. Then the starter went bad. I dont have a clue. Can you help?

There are three separate electrical circuits on your tractor - ignition, charging, and starting (plus lights if you have them make four). All are independent of each other. Thus the starter circuit and the charging circuit have absolutely nothing to do with a lack of spark. The ignition goes from the hot terminal to the ignition switch thru the resistor to the coil. Thru the coil and the springy thing to the points and when the points are closed to ground. Use a multimeter to check voltage thru all those connection. With the dist coil assembly off of the tractor check continuity thru the coil and points to ground with the points closed and no continuity with the points open.

When you changed 6 to 12 volt did you run a resister to coil it my be shot. Did the starter go bad all at once or was it a slow death? Maybe the starter just needs a good ground

no spark? check the points for .015 gap on all lobes.. then if no spark check to see if you have power to the coil from the switch and resistor(s).

is this the oem 6v coil.. or a newer 2.5ohm coil.. if a newr coil the ballast resistor is all you need. if an older coil, then you need the ballast resistor plus another converting resistor to bring primary current down below 4a.

in any case.. check power to coil.. use a jumper wire fromt he battery if needed. if power tot he coil and no spark, use an ohm meter to check the dizzy with power disconnected and spin her over to see if points are opening.. can look for a shorted capacitor that way. test lamp works too.. just insert inline with power from battery.. lamp on always.. points or cap shorted.. no lamp.. points are not closing. or something is open..

soundguy

" Then the starter went bad. I dont have a clue."

Well, given that you haven't told us any symptoms, I don't have a clue either. Does it spin & the bendix doesn't engage? What exactly happens when you press the starter button? Tried jumping it? (see tip # 43 before you do that)

Assuming that the bushings & advance weights are ok, & that you have correct voltage to the coil,( do you? What is it?) the most common electrical failure (no spark, weak spark) points on the frontmount are:

1. The insulator under the brass concave head screw.

2. The insulator at the end of the points where the copper strip attaches.

3. The copper strip is broken or grounded to the plate.

4. The condenser wire grounding.

5. The pigtail/tab not making contact.

6. Incorrect positioning of the spring clip on the plate causing the pigtail to ground.

7. Incorrect seating of the coil on the distributor due to a loose bail or no gasket; the coil must not move at all.

8. Water/moisture inside the cap due to gasket failure or the absence of a gasket.

9. Dirty/corroded/incorrectly gapped points

10. Burned rotor, cracked/carbon tracked cap.

Unless the coil is cracked or shows a dead short, chances are it's fine; square coils rarely fail cold. Pull the distributor & do a continuity check.

First, make sure your meter/light works (don't ask....)

Next, dress the points by running a piece of card stock or brown paper bag through them. New points sometimes have an anti-corrosive dielectric coating on them & old points can corrode or pick up grease from a dirty feeler gauge or excessive cam lubricant. Then, check the gap at .015 on all 4 lobes.

Now, follow these steps:

1. Coil off, cap off, points open. One probe on the brass screw & the other on both sides of the open points. On the side closest to the cam, you should have continuity. Not on the other side! If you do, you will also have continuity everywhere because the points are grounded.

2. Coil off, cap off, points open. One probe on the brass screw & the other anywhere on the body of the distributor. You should have no continuity! Now, rotate the tang on the distributor....as the points open & close, you have continuity (closed) and lose it when they open.

3. Coil on, cap off, points open. One probe on the lead on the top of the coil, the other on the cam side of the open points. You should have continuity!

4. Coil on, cap off, points open. One probe on the lead on the top of the coil, the other anywhere on the body of the distributor. You should have no continuity!


At this point, I just put the distributor, coil & cap all back on the tractor as a unit. The reason I do this is because it is real easy to get the cap or coil mis-aligned trying to put it back together one piece at a time & the result is something gets broken or you get a ‘no spark’ problem.

Post back w/ results & any other questions.

50 Tips

John......would it surprize you to learn that yer starter motor has 'nuttin' to do with yer sparkies???

Follow the VOLTS. Check fer volts at the top of the squarecan ignition coil terminal. It will be either about 12V or 3V or ZERO volts. Exact value of volts is NOT CRITICAL. Iff'n you have ZERO volts, guess what??? You ain't gonnna have enny sparkies.

So check for volts around yer "infamous ballast resistor" 3-terminal "T" board under yer amp-meter. Again can be either 12V or 3V or ZERO. Iff'n you have ZERO volts, guess what??? While you were futtzin'round with changing yer starter motor, you MISWIRED the volts wire to the terminal board.

You don't have a VOLTMETER??? Gitt'cha one at yer local hardware store. $10-20 (cheap) .......Dell, yer self-appointed sparkie-meister

ok,you changed the starter and now no spark ,if I understand correctly,And this was on a running tractor.you've have probably done one of two things .one ,if you have changed to a key switch start you have put the ign wire on the wrong post on solenoid or forgotton to hook it up,or two if you are using the original safety switch and starter button,you either forgot to hook up ignition wire,broke it or have it on the wrong side of safety switch.one other possibility,battery is weak, and it takes so much power to run starter ignition cant fire, it simply takes all the power to run starter.
My opinion of course,and yes, they will crank over with ignition off or disconnected.

"There are three separate electrical circuits on your tractor - ignition, charging, and starting (plus lights if you have them make four). All are independent of each other."

I disagree. The starter turns the crank , that turns the rotor, that makes the sparkies jump at the cap nipples, that makes the sparklers light up.

Yes , however the cam opening the points, is not an electrical, but a mechancal thing. As Dell said if you ain't got voltage to coil it won't have "spark"

3 main circuits...joe 40 years tracing electrons.

The tractor will run without a starting system (use a hand crank) And it will run without an operating charging system.

This post from Bruce is priceless.

I have printed a copy,framed it, hung it on the barn wall with a light shining on it 24/7.

I'll bet I've used it a dozen times, and read it hundreds.

Tnx Marc! Kind of you to say so.