no spark in 2n

Was hogging and about half way thru tractor died without warning. It has no spark at plugs, but does have spark at points. When jumping them with screwdriver. New points, condenser, rotor,& plugs. It is a 1947 2 N. Ideas? All plug wires test ok with ohm meter. Don't see anywhere points are grounding out. About ready to pull distributor out of parts tractor. But find it strange it died without warning.
 
Are the points opening and closing as the engine rolls over?
You can check that by measuring voltage at the wire on top
of the coil. Should read battery voltage points open, about half
that when the points are closed. Roll the engine by hand, key on.
Don't forget to turn the key back off. No need to ask.
New points sometimes slip or have a poorly made rubbing
block that wears down very quickly when it gets hot.
 
Am I correct in assuming that turning the engine by hand (generator belt) that, that technique would work for an 8N Front Mount also?
 
A true root cause problem solving method is the best approach to any problem. Don't just start guessing and replacing parts. Tell us more. Is it the OEM 6V/POS GRN electrical system or has it been switched over to 12V/NEG GRN? Either way, if it isn't wired CORRECTLY, you will have issues. Also, sometimes fellas surmise they have an electrical problem and it turns out to be a fuel related issue or vice versa. Shorting out points with a screwdriver? You may have more issues now doing that. Use your VOM to test with, continuity first on the distributor OFF the tractor. Did you time the unit when you did a tune-up? Are breaker points set at .015"? Are plugs gapped at .025" - .028"? With the unit off, cap off, points open, VOM set to continuity, one probe on lobe side of points, the other probe to opposite side. There should be continuity. Closed will give continuity. If you have continuity with points open, then you will anywhere else on the base to ground as there is a short somewhere. If unit passes, mount to tractor, place probe on the ballast resistor LH terminal, that is where the coil wires connects to, and place the other probe anywhere to ground, and turn key switch ON but do not crank engine. You should have continuity. If so, switch VOM to VDC, repeat the test. You should read battery voltage with points open and half that with points closed.

TPD
 
"Are the points opening and closing as the engine rolls over?
You can check that by measuring voltage at the wire on top
of the coil. Should read battery voltage points open, about half
that when the points are closed. Roll the engine by hand, key on."

May I also assume that (1) The clutch should be clamped down to disengage? (2) That the spark plugs are removed to enable
easier turning of the engine? (3) That the analog multimeter is grounded via the Black (neg.) lead to a ground despite the
tractor having a positive ground? Or, does the multimeter have to use Red (pos.) to a ground?
 
Blocking the clutch and pulling the plugs will make it easier to
turn the engine. I use a hand crank so I don't bother with them.

If you use an analog meter, you will need to hook it up with the
correct polarity. Red to ground for a positive ground system.
With a digital meter it wouldn't matter except it would read
negative numbers instead of positive numbers if reversed. In this
instance, when the engine is not running, digital would be fine.
 
Thanks for the input and as soon as I get caught up on chores I'll put them to use. It's a stock tractor that I've been using for decades. I did have it apart to put sectors in it. I'll be sure to look at the before pics I took. But it did start right up and hogged about and acre and a half before it died.
 
My volt meter reads 6.5 volts at battery. Reading from the coil wire and rolling engine over to open points it reads 6.5 when points are open it drops all the way to .54 when closed. That seems like a pretty big drop off to me. Is there a way to check battery? Other than volt meter across terminals?
 
Tested for continuity between points when open and none was found. So apparently not grounded out. Haven't found any breaks in the straps either on the points or connecting the condenser to points.
 
All tested ok. Except for voltage drop when testing ballast resistor terminal. The voltage only dropped to 5.74 not half with points closed. 6.3 when open.
 
Bill in Ark, is this 5.74v reading on the coil side of the resistor?
If so, it should be the same point, electrically, as the top of the
coil and you said you only had .54v there? Do you have any
other resistors on the tractor or just the original ballast resistor?
 

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