On the conversions I've done to Petronix, on tractors or automobiles, I always use their wires as well as their suggested flamethrower coil for the electronic ignition system. Never a failure. Good test procedure on the coil my friend.
Great video. My tractor just quit on me this morning. Checked everything and then found your video. It was the exact same problem. Thanks for your help!
Wow, great video! I am having an issue with my car. It misfires when it’s gets warm and looses all power. Narrowed the problem down to ignition. I will test the coil as you described. Thank you!
@@Eli-lx2fq The Problem actually proved to the brand new MSD ready to run distributor. Electronically dumping or adding as much as 12 degrees of timing randomly! Mechanical advance was fine. A friend had it on his distributor machine. I was able to get this warranted. Has anyone else experienced this, that you know of?
I had my 1951 Ford 8N tractor converted to 12 volts back in the early 90's. The coil does not have internal resistor because it connects to an external resister called the ballast (white ceramic piece screws ro the firewall) that wires connect to from the coil. How do you test resistance to see if the coil is good or bad in my case? Im sure a lot of guys have external resistance coils still on their tractors that may have issues. Thanks for responding back. THUMBS UP!!!
There is no internal resistor. The resistance of the coil is determined by the length of the wire, the diameter and the composition of the wire. Thinner wire with more turns will read higher than thicker wire. Shorted turns will cause low resistance as well as. A static resistance test is ok, but a better test would be a ring test or better yet an inductance test compared to a known good coil. A small resistor in series is not a bad idea on either coil as of the key is left on and the contacts are closed you have continuous current flowing through the coil and creating heat. Once the points are interrupting the current flow you are getting an AC pulse and this is where inductance and inductive reactance (resistance) comes into play. The higher the RPM the higher frequency of the pulse and the more reactance. Overall the video is a good basic test.
Look to see if you have any wires from the coil that lead up to the swite ceramic piece on the firewall. That creates resistance needed for a coil that has no internal resistance. My coil once split in two (cracked) and I lost resistance, so I had to buy another ceramic resistor from Ford tractors. I could've at that point just bought a coil with internal resistors but did not know the difference at the time. But my older coil works well with external resistor. I have a '51 Ford 8N.
@@TheKiltedHomesteader Because in general, the secondary circuit on an ignition coil will be in the range of 6000 Ohms to 16,000 ohms, depending on the coil's original specification. The Primary circuit should be tested on the 200 Ohms setting on the meter. Same reason. Coil Primary circuits in general will range between 0.2 to 3 Ohms, again depending on the coil's original specification. Just my experience but electronic ignition modules (Pertronics, GM HEI, etc.) don't play well over time with higher resistance on coil Primary circuits. I've learned from research (and from actual doing) that most electronic ignitions that use a Hall Effect signal generator in the distributor work better & longer if the coil Primary resistance is 1.5 Ohms or less. Ideally (at least as far as HEI modules are concerned, Pertronics is similar, depending on model) 0.2 to 0.8 original specification for Primary resistance is best. If you look at Pertronics own website & check the coil Primary specs on their later-model Flame Thrower 2 & 3, they are in those lower ranges. I found it very interesting that both your Primary & Secondary circuits went "open' at the same time. I've never come across a coil that did that. They most usually develop high Secondary resistance over time or the Secondary just goes "open". That's mostly due to time, heat, & the fact that the Secondary can put out 20,000 to 50,00 volts. That's a lot of stress over time & it will break down eventually.
I don't think the secondary winding is connected to the primary winding. To test the secondary you have to connect from the center terminal to the body of the coil which is grounded by the mount.
Lucas coils. The Secondary winding is in series with the Primary. Why? This improves the spark at the plug. The 300 volts induced in the Primary at the contact break being added to the Secondary voltage. This effect is known as auto transformer action. Now, please take note. A standard Lucas wet (oil filled) coil is 2.7 ohms. Work on 3 ohms, but check current. On 12V you are looking for 4 AMPS. This is a standard coil without an external resistance. Remember that Lucas coils are wound for positive ground which is negative spark. Don't try running negative earth. Yes it will work for a while, but you must have a negative earth wound coil.
Also the centre terminal of the coil is grounded by the spark plug. The case is fully insulated from both the primary and the Secondary windings of the coil. If you get a reading through the case then you have a faulty coil. Hope I haven't confused you too much. 😊
I don't believe there is a resistor in the coil. The resistance reading on the primary should be under 1 ohm, because there is a small amount of coiled wire compared to the secondary. To test the secondary. Move the meter to 20K ohms. The secondary has many more coils of wire and would have much more resistance, it should read 5k to 10k on many coils. General rule.
Its One Point Ohms... Not Point One Ohms Resistance showing on the Meter, Sir. People... ALWAYS Purchase an AUTO RANGING Digital Meter! Harbor Freight GIVES THEM AWAY!!
Well done, a great video showing how to test a coil. A simple explanation that even I could understand. Thank you.
Great info; going to test the spare coil I have for my 1931 Ford Model A.
On the conversions I've done to Petronix, on tractors or automobiles, I always use their wires as well as their suggested flamethrower coil for the electronic ignition system. Never a failure. Good test procedure on the coil my friend.
Great video. My tractor just quit on me this morning. Checked everything and then found your video. It was the exact same problem. Thanks for your help!
That’s awesome! Thank you for watching.
Wow, great video!
I am having an issue with my car. It misfires when it’s gets warm and looses all power.
Narrowed the problem down to ignition.
I will test the coil as you described. Thank you!
You,friend have a short between the steering wheel and driver’s seat.😂
@@Eli-lx2fq lol. Thanks
@@Eli-lx2fq
The Problem actually proved to the brand new MSD ready to run distributor. Electronically dumping or adding as much as 12 degrees of timing randomly!
Mechanical advance was fine.
A friend had it on his distributor machine.
I was able to get this warranted.
Has anyone else experienced this, that you know of?
Great video, thanks
That was the best example I have found thanks!
Awesome and thanks for watching!
Great video my Friend !
I had my 1951 Ford 8N tractor converted to 12 volts back in the early 90's. The coil does not have internal resistor because it connects to an external resister called the ballast (white ceramic piece screws ro the firewall) that wires connect to from the coil. How do you test resistance to see if the coil is good or bad in my case? Im sure a lot of guys have external resistance coils still on their tractors that may have issues. Thanks for responding back. THUMBS UP!!!
There is no internal resistor. The resistance of the coil is determined by the length of the wire, the diameter and the composition of the wire. Thinner wire with more turns will read higher than thicker wire. Shorted turns will cause low resistance as well as. A static resistance test is ok, but a better test would be a ring test or better yet an inductance test compared to a known good coil. A small resistor in series is not a bad idea on either coil as of the key is left on and the contacts are closed you have continuous current flowing through the coil and creating heat. Once the points are interrupting the current flow you are getting an AC pulse and this is where inductance and inductive reactance (resistance) comes into play. The higher the RPM the higher frequency of the pulse and the more reactance. Overall the video is a good basic test.
Thank you for the feedback! All information is greatly appreciated.
those blinking gnomes.....
“The coil never goes bad.” I have replaced MANY, same with the condenser!
How do I know if my coil has the internal resistor or not?
By getting the makers specs. Usualy a part number can help.
Look to see if you have any wires from the coil that lead up to the swite ceramic piece on the firewall. That creates resistance needed for a coil that has no internal resistance. My coil once split in two (cracked) and I lost resistance, so I had to buy another ceramic resistor from Ford tractors. I could've at that point just bought a coil with internal resistors but did not know the difference at the time. But my older coil works well with external resistor. I have a '51 Ford 8N.
You need to move the ohmeter resistance to 20k for second test.
Why is that?
@@TheKiltedHomesteader Because in general, the secondary circuit on an ignition coil will be in the range of 6000 Ohms to 16,000 ohms, depending on the coil's original specification. The Primary circuit should be tested on the 200 Ohms setting on the meter. Same reason. Coil Primary circuits in general will range between 0.2 to 3 Ohms, again depending on the coil's original specification.
Just my experience but electronic ignition modules (Pertronics, GM HEI, etc.) don't play well over time with higher resistance on coil Primary circuits. I've learned from research (and from actual doing) that most electronic ignitions that use a Hall Effect signal generator in the distributor work better & longer if the coil Primary resistance is 1.5 Ohms or less. Ideally (at least as far as HEI modules are concerned, Pertronics is similar, depending on model) 0.2 to 0.8 original specification for Primary resistance is best. If you look at Pertronics own website & check the coil Primary specs on their later-model Flame Thrower 2 & 3, they are in those lower ranges.
I found it very interesting that both your Primary & Secondary circuits went "open' at the same time. I've never come across a coil that did that. They most usually develop high Secondary resistance over time or the Secondary just goes "open". That's mostly due to time, heat, & the fact that the Secondary can put out 20,000 to 50,00 volts. That's a lot of stress over time & it will break down eventually.
@@The13thSword thank you for the information!
@@TheKiltedHomesteaderbecause the resistance is much higher and needs to be measured on a higher scale.
I have to find a nomes equipped meter
Let me know if you find one ; D
My primary show 5 ohms but secondary shows infinite. Does that mean the coil is bad?
Yes
I don't think the secondary winding is connected to the primary winding. To test the secondary you have to connect from the center terminal to the body of the coil which is grounded by the mount.
Trust me, this way works!
Lucas coils. The Secondary winding is in series with the Primary. Why? This improves the spark at the plug. The 300 volts induced in the Primary at the contact break being added to the Secondary voltage. This effect is known as auto transformer action. Now, please take note. A standard Lucas wet (oil filled) coil is 2.7 ohms. Work on 3 ohms, but check current. On 12V you are looking for 4 AMPS. This is a standard coil without an external resistance. Remember that Lucas coils are wound for positive ground which is negative spark. Don't try running negative earth. Yes it will work for a while, but you must have a negative earth wound coil.
Also the centre terminal of the coil is grounded by the spark plug. The case is fully insulated from both the primary and the Secondary windings of the coil. If you get a reading through the case then you have a faulty coil. Hope I haven't confused you too much. 😊
Those damn gnomes created infinite Ohms.
I have ford 3000 tractor it dies at 1400 rpm any ideas
I don't know much about that machine.
@@TheKiltedHomesteader ty for reply
Replace your ballast resistor
😎
I don't believe there is a resistor in the coil. The resistance reading on the primary should be under 1 ohm, because there is a small amount of coiled wire compared to the secondary. To test the secondary. Move the meter to 20K ohms. The secondary has many more coils of wire and would have much more resistance, it should read 5k to 10k on many coils. General rule.
Yes, some coils have built in resistors and some do not. They make them both ways and for different applications. Thank you for watching.
Should have named the video the impotent nome!😂
lol
KAL BO OOO,---SUPUTTT,!!!!
Its One Point Ohms... Not Point One Ohms Resistance showing on the Meter, Sir. People... ALWAYS Purchase an AUTO RANGING Digital Meter! Harbor Freight GIVES THEM AWAY!!
Thanks for the info.
Why all the bs just what is the value of the coil 2 min video
Thanks for watching!