Ignition (secondary) Circuit Problem...

**miked** · October 12th, 2012 09:15 PM

conventional contact point gas engine (willys engine)

Engine ran at idle for about 3 minutes then just went dead. tried restarting, just a click on the starter. unbolted starter then wired directly to battery and after some hesitation, came back to life. now starter turns over, but engine wont start.

Situation report:
1. Ammeter stays at zero when switched on (previously, ammeter swings to discharge side when "switched On". tried wiggling and reconnecting all connections for possible corrosion still the same)
2. no spark at the ignition coil secondary
3. Got battery voltage at ignition coil positive and negative terminals (with a spark on the points when opened).
4. ignition coil primary resistance = 4 ohms
5. ignition coil secondary resistance = 8,100 ohms
6. ignition coil to distributor hi-tension wire resistance = 1017 ohms.
7. no carbon tracks on distributor housing. looks good visually.

comments/inputs please.

**Phoenix67** · October 12th, 2012 09:28 PM

did you also check the fuel? tumakbo ng three minutes...means merun fuel sa baso (carburator reservoir) but it was probably not replenished (fuel leak, kulang ang fuel, no fuel na sa tank, putol ang fuel line, or barado ang fuel line are among the possible cause).

if fuel is not the issue, kalasin mo ang isang spark plug and check if merun spark pag-niredondo mo ang engine. if wala, your ignition coil could be faulty....try mong manghiram ng working coil and replace it muna to test the engine again.

**miked** · October 12th, 2012 09:34 PM

oops, forgot to tell lotsa fuel....item #2 says no spark at ignition secondary therefore no spark also on all 4 spark plugs.

got battery voltage on the primary winding, switch side and ground side.

**tip_tipid** · October 12th, 2012 11:18 PM

1. check that the distributor contact point asm is not corroded and properly gapped.
2.. check that the distributor contact point condenser is not bad.
You can try to create spark just by turning the ignition switch to on and manually operate the contact point. The point should be initially at closed position.

**jick.cejoco** · October 13th, 2012 06:35 AM

Originally Posted by miked

conventional contact point gas engine (willys engine)

Engine ran at idle for about 3 minutes then just went dead. tried restarting, just a click on the starter. unbolted starter then wired directly to battery and after some hesitation, came back to life. now starter turns over, but engine wont start.

Situation report:
1. Ammeter stays at zero when switched on (previously, ammeter swings to discharge side when "switched On". tried wiggling and reconnecting all connections for possible corrosion still the same)
2. no spark at the ignition coil secondary
3. Got battery voltage at ignition coil positive and negative terminals (with a spark on the points when opened).
4. ignition coil primary resistance = 4 ohms
5. ignition coil secondary resistance = 8,100 ohms
6. ignition coil to distributor hi-tension wire resistance = 1017 ohms.
7. no carbon tracks on distributor housing. looks good visually.

comments/inputs please.

your ignition coil resistance is a bit too high and if there is spark at the gap between the points is an indication your condenser is shorted. with an analog (needle type) multi meter set in resistance mode, check resistance in forward then in reverse. the needle should move right then collapse back to the left, reverse the procedure and the same result should be expected. if the needle does not behave as described, the condenser is either open or shorted. if you have a tach/dwell meter, the points dwell should be within the 52 degrees

**miked** · October 13th, 2012 10:27 AM

Originally Posted by jick.cejoco

your ignition coil resistance is a bit too high and if there is spark at the gap between the points is an indication your condenser is shorted. with an analog (needle type) multi meter set in resistance mode, check resistance in forward then in reverse. the needle should move right then collapse back to the left, reverse the procedure and the same result should be expected. if the needle does not behave as described, the condenser is either open or shorted. if you have a tach/dwell meter, the points dwell should be within the 52 degrees

which resistance? primary or secondary? an internet source tells about 0.5 -1.0 ohms primary resistance (w/o a ballast resistor) and a maximum of 4.0 ohms (w/ ballast resistor). secondary winding ranges from 9,500 ohms - 10,000 ohms.
btw, no idea if coil has an internal ballast or not.

tried to connect a voltmeter on the ground side (distributor side) of the coil and cranked engine. voltage reading ranges from 7.++ to 12.++ while cranking.

**t2erns** · October 13th, 2012 11:53 AM

is that coil ground pulsing? my basis for computing a wire resistance (high tension wire to distributor) is 1k ohms per inch

**jick.cejoco** · October 13th, 2012 03:05 PM

Originally Posted by miked

which resistance? primary or secondary? an internet source tells about 0.5 -1.0 ohms primary resistance (w/o a ballast resistor) and a maximum of 4.0 ohms (w/ ballast resistor). secondary winding ranges from 9,500 ohms - 10,000 ohms.
btw, no idea if coil has an internal ballast or not.

tried to connect a voltmeter on the ground side (distributor side) of the coil and cranked engine. voltage reading ranges from 7.++ to 12.++ while cranking.

that's correct! the primary resistance is usually less than or around one ohm. if you want to know if the primary circuit has an external or internal (built-in) resistor, check the voltage at the ignition coil positive terminal. but since you stated you have a vintage willys overland engine, the primary circuit is that of two: one direct battery voltage (start mode) for quicker start ups and one ballasted run circuit once you release the ignition switch to run mode, then you have an ignition coil that has no internal resistor

**miked** · October 13th, 2012 04:46 PM

Originally Posted by t2erns

is that coil ground pulsing? my basis for computing a wire resistance (high tension wire to distributor) is 1k ohms per inch

yap.pulsing voltage. an internet source again says that it should cycle from 0 volt to 12 volt.

**miked** · October 13th, 2012 04:48 PM

Originally Posted by jick.cejoco

your ignition coil resistance is a bit too high and if there is spark at the gap between the points is an indication your condenser is shorted. with an analog (needle type) multi meter set in resistance mode, check resistance in forward then in reverse. the needle should move right then collapse back to the left, reverse the procedure and the same result should be expected. if the needle does not behave as described, the condenser is either open or shorted. if you have a tach/dwell meter, the points dwell should be within the 52 degrees

i have two spare condensers. swapped them both, still the same. contact point gap is right at 0.020 inch.