heethenharley
Member
how do I test cool and are the ohms for a good on
coil testing
- Thread starter heethenharley
- Start date
I found this in the self help section.
If you want to test the coil. First remove it and the wires. You have to two posts where the wires go. This is the primary side. Connect the OHM meter to them. You should get about 2.5 to 3.0 OHMs. Secondary side is where the spark plug wires go. Connect the OHM meter to them and you should get around 10,000 to 12,500 OHMs
If you don't have a OHM meter here is another way to check.
If you want to "bench" test a coil, remove wires, attach a hot 12 volt to the battery (batt, +, etc.) terminal. Then attach a wire to the ignition (ign) terminal and touch ground and remove. Should throw a spark from the high tension lead with each application of 12v and removal. The ground wire basically imitates the function of the ignition points/module. If the high tension lead terminal is gapped a reasonable amount from the engine, there should be a bright white spark. Weak or orange spark indicates (low voltage...or) bad coil output.
If you want to test the coil. First remove it and the wires. You have to two posts where the wires go. This is the primary side. Connect the OHM meter to them. You should get about 2.5 to 3.0 OHMs. Secondary side is where the spark plug wires go. Connect the OHM meter to them and you should get around 10,000 to 12,500 OHMs
If you don't have a OHM meter here is another way to check.
If you want to "bench" test a coil, remove wires, attach a hot 12 volt to the battery (batt, +, etc.) terminal. Then attach a wire to the ignition (ign) terminal and touch ground and remove. Should throw a spark from the high tension lead with each application of 12v and removal. The ground wire basically imitates the function of the ignition points/module. If the high tension lead terminal is gapped a reasonable amount from the engine, there should be a bright white spark. Weak or orange spark indicates (low voltage...or) bad coil output.
heethenharley
Member
thank you
You're welcome, good luck and let us know of your findings.
heethenharley
Member
I will ,when I hook up ohm meter to primary so put ground lead off the meter to ground or to ignition side of the coil and positive to the 12 volt side ?
biscuit
Junior Member
Good call Jack.
O.P:
An ignition coil is basically a Transformer. Just like the one on a pole. 2 UNCONNECTED windings with one inducing voltage into the other.
Testing the primary windings and the secondary windings is as Jack said.
This proves the integrity of both sets of windings.- NO open circuits ( broken wires)
ANOTHER test one can do is to prove there’s no SHORT CIRCUITS between the primary and secondary windings.
Both of these windings are insulated from each other by protective dielectric coverings. If this breaks down, it will cause a short circuit between these two sets of windings.
Put your voltmeter on “OHMS” or on the setting that makes a beep to indicate continuity. Connect one voltmeter lead to the primary wire and the other to the secondary output wire. You will do this twice to test each wire.
If theres a SHORT CIRCUIT; you’ll get a very low resistance (OHMS) reading. Or a beep for as long as the leads are attached.
Means coil bad. New one required.
If you get NO beep ; or show the infinity symbol on the voltmeter that means NO connection between the windings.( HIGH resistance).
Good results.
Happy days.
O.P:
An ignition coil is basically a Transformer. Just like the one on a pole. 2 UNCONNECTED windings with one inducing voltage into the other.
Testing the primary windings and the secondary windings is as Jack said.
This proves the integrity of both sets of windings.- NO open circuits ( broken wires)
ANOTHER test one can do is to prove there’s no SHORT CIRCUITS between the primary and secondary windings.
Both of these windings are insulated from each other by protective dielectric coverings. If this breaks down, it will cause a short circuit between these two sets of windings.
Put your voltmeter on “OHMS” or on the setting that makes a beep to indicate continuity. Connect one voltmeter lead to the primary wire and the other to the secondary output wire. You will do this twice to test each wire.
If theres a SHORT CIRCUIT; you’ll get a very low resistance (OHMS) reading. Or a beep for as long as the leads are attached.
Means coil bad. New one required.
If you get NO beep ; or show the infinity symbol on the voltmeter that means NO connection between the windings.( HIGH resistance).
Good results.
Happy days.
[QUOTE="joel
This is a 2 part test, spark and recoil.
If your arm is long enough, you could hold the plug wire on your tongue and momentarily hit the start switch.
You first!
This is a 2 part test, spark and recoil.
If your arm is long enough, you could hold the plug wire on your tongue and momentarily hit the start switch.
You first!