Learn how to test an ignition coil and check if it needs replacing.
Tools/Parts Required
- Ignition Coil
- Multi-Meter
Step 1.
Set your Multi-Meter to 20K Ohms and connect the black ground lead to the spark plug wire.
Step 2
Touch your positive lead to each of the terminals on the ignition coil a good coil should read close to 9k Ohms, If your coil has more then 12-14K Ohms resistance then this is likely it needs replacing. As the greater the resistance of the coil the weaker the spark.
Step 3
There is some variation in Victa ignition coils, Some include fixed ignition modules these coils read around 13Kohms new.
Hi Guys,
Thanks for the great video on Victa coil replacement. A question…I tested my coil as per your information and my muiti meter reading came out at 8.39. I take it that this reading also indicates a “fail” for this coil. I note that if the reading is 9.51 that’s good, but if greater than 11 or lower than 9, these readings indicate “fail” and therefore the coil should be replaced. Just seeking confirmation that I understand the readings OK.
Anyway, I’ve gone online and ordered a new coil from Push Mower.
Regards,
Ken
Hi Ken
Glad the videos are helpful, for readings below 9 you may have a slightly different coil, the replacement coils are design for power torque engines between 1988-1996, you can tell if your mower may have a different setup up by looking at your current ignition system, if there is a small silver component attached to the block beneath the carburetor that is the ignition module (which is usually Incorporated into the coil in most models) and that may be faulty causing failure of the ignition system.
Testing coils with a multimeter is hit or miss. Just because you get the right resistance reading does not mean the coil is good. You may get a reading that is spot on but the coil may still be bad. Coils run at high voltage and this can jump across turns giving you a weak spark. Similarly, testing for spark on the spark plug has to be done on a proper spark tester. A spark plug under compression will throw a weaker spark (or none at all) whilst under no compression may appear to work perfectly.
Great videos legends
Followed your video to test my coil. I got a reading of around 13 ohm, I bought a new coil and tested that too, it also reads 13 ohms….am I missing something? Is the new coil faulty?
Hi
Some Victa Coils are slightly different to these ones and come with an included ignition Module, These coils read about 13 KOhms I would think that is the coil you must have. They have a small rectangular protrusion the others do not.
Oh okay, thanks for the info :)…you should put that in the info of your tutorial.
My ignition module is an all in one module with permanent wires, and spark plug lead and boot, and big metal thingy already installed.
Oh well I guess I just bought a new module for nothing 🙁
So can you help with my problem. I get no spark or sometimes a very weak and not visible spark. I have removed the earth wire from the carby…still no spark.
Could the problem be a short cord thats not spinning the flywheel fast enough?
It could be slow rotation of the flywheel, it could also be too large an air gap between the ignition coil and the flywheel magnets.
Hi I test already my ignition coil and ignition module by following your video instructions. I found out all are fail. I look from your website about the coil you have nothing for victa. Where can I buy that one?
We will have some coils available in about a week, If you email me via the contact us page I can let you know when they are available.
Hello admin,
I’m currently repairing a self-propelled Victa 550. I’ve done the above tests and the readings are 4.26 from both terminals. I’ve interpreted that as meaning there is sufficient current passing through the terminals? Also, is it possible to pull the ignition cord out of the original coil? The lawnmower I have has had it’s coil cut (for one reason or another) and I wanted to know if I would destroy the coil if I pulled it out or should I just solder another length of cable to it? Your help is greatly appreciated.
Hi Aleks
Does your coil have the separate ignition module or is it molded to the coil, you can tell by the square shape on some coils or the lack of ignition module normally located below the carburettor. If the module is included i would say your coil has a short and you are picking up the resistance of the module. otherwise it is a uncommon reading but does suggest the coil would be working.
some coils have a lead that unscrews if you twist it, others are molded into the coil. if it does not twist off i would suggest soldering on a new length rather then trying to remove the old lead.
Hey Lachlan,
I purchased a bunch of gear from you guys and appreciate the advice you have given me. I got her started after being left for close to 20 years and the motor was oscillating between over and under revving. Then when I tried starting her again the pull chord was just pulling out freely without any resistance (until the very end of the chord I may have been getting 2-4 oscillations). What are your thoughts? I also found that the head gasket had fuel/oil through it in, is this normal?
Many thanks, Aleks
Hi Aleks
If you would like to send a picture of the head gasket to “support@pushmowerrepair.com” I can tell you whether or not it is normal, It sounds as if it is not sealing properly causing a loss of compression
Regards
Lachlan
Hi if I do the test as instructed I get a figure of 6 if I go from plug lead to module I get a figure of 11. Is the coil and module good? I thought 13 would be best and numbers higher than 13 would indicate bad coil
A reading of 6 when testing the coil alone suggests it has an internal short that is lowering the resistance this would also suggest that it may be faulty
Hi mate. Do you still sell this ignition coil?
Hi Steven
We are unable to source the coils at the moment.
Hi, I have a VICTA VC 160 two stroke lawnmower which I bought in 1970. You read correctly. It is 46 years old. I have a weak spark. Could a coil still be available? Could I change to CDI if I am using the correct terminology.
Please advise me.
Pieter de NYSSCHEN
South Africa
Hi Pieter
You could upgrade to electronic ignition by removing the points and installing an ignition module, I believe a coil will be available that is compatible with the module I do not know if the coil for the points ignition is still available, If you contact me via the contact us page I can help you with the parts and options available.
Hi, I have tested my victa mower coil as per your video and get a reading of 4.2 but still get no spark is this reading too low?
Hi
Yes 4.2 is too low it is likely your coil is shorted internally cause the spark fault
I have tested coils which have come up at 8.14. I have connected them to the place in the mower with the gap provided by the business card. Without putting the engine back into the mower, I have turned the mower by hand with the magnet passing the coil and received a mild shock at the end that is attached to the spark plug. In the past I have had difficulty putting the engine back and then getting little result. The above way I thought may lessen the work load.
My question is, does the mild shock I get good enough to indicate it will satisfactory when I fix the engine back into the mower. I guess I am asking does the speed provided by pulling the cord create enough spark to make the mower work.
Hi Graham
The mild shock you receive indicates that the coil is providing a high voltage to the plug, This does eliminate problems such as completely dead or shorted coils, But it is not a fool proof method, Many coils that do not produce a strong enough spark to run an engine will still be capable of providing a good electric shock if held while the motor is spun.
Hello Lachlan,
I have a Victa 160, Series 70 Mark 4 mower that is not generating a spark. I have bought a second hand set of coil and points but still no spark. Kill wire is disconnected. My original coil is the shiny black one with Victa on top and had a fixed (nonadjustable) mounting plate. The replacement one is a dull black with a yellow sticker that has FMV 83 on it and its mounting plate is adjustable on both sides. Both have tested ve to continuity. The old one gives no resistance reading but the replacement one gives a reading of 5.75K ohms. I presume from your information that this is a failure as it should be up around 9-10K ohms. The strange thing is that when I first fitted the replacement coil set without checking the timing there was a very faint spark, just from winding the flywheel slowly by hand. I decided that the timing may be out so reset it using yours and others instructions only to result in no spark at all. I tried different positions of the mounting plate to flywheel but still no spark. I note that there is some conflict in point/breaker/contact gap recommendations with your website suggesting 0.685mm and others indicating 0.50mm. I have tried both as well as changed the spark plug to no avail. I have therefore concluded that the replacement coil is faulty. One other thing I noticed when setting the timing at 3mm btdc then the point gap on the replacement coil set, the points/breakers/contacts don’t actually make contact when you fully rotate the crankshaft. Is this normal? Can replacement coils still be purchased for this vintage of Victa motor? Your comment and advice would be greatly appreciated.
Hi Ed
A reading of 5.75k Ohms is not a bad reading for the older coils, Each coil has a different range of acceptable readings, I cannot source any replacement coils for the older models at the moment.
The issue is most likely due to incorrect setting of the points, The contacts should be touching each other for most of the rotation and only seperate when the spark needs to be produced. A good animation can be seen here https://www.youtube.com/watch?v=W94iksaQwUo (System is less complex on the mower but principals are the same).
Hi Lachlan,
Thank you for your advice on this. You were so right, it was all in the points setting. Dummy me had set the points gap at 3mm btdc and there was no way they were ever going to close. So I did the following: At 3mm btdc I set the points at just open (0.050mm). I rotated the crankshaft to tdc (exactly with cam in line with key way). I readjusted points gap to 0.50mm and refitted the flywheel. Checked for spark to find one was there but not as strong as I expected. I removed the flywheel, loosened the coil plate and rotated that slightly, then tightened it back up. Refitted the flywheel and checked the spark which was stronger than before. I thought that was good enough so put everything back together, fuelled the mower, primed the G4 carb and with two pulls it roared into life. I am so pleased I have been able to get this trusty old mower going again. I have two ride ons and two push mowers and this is the only one that will mow grass that is taller than itself with ease. Its a gutsy old mower. What a beast!
Thank you so much for your help.
Hi,
Thank you for the very informative coil testing video! I am trying to resurrect a 2011 Victa Tornado 2230, 2 stroke line trimmer.
After carefully stripping down and flushing out the carb, I cleaned the tank and using fresh fuel and 2 stroke oil mixed to directions provided and replaced the spark plug but I am still unable to get the motor running.
The coil tests at around 1.8Kohms and the spark is weak, intermittent and sometimes barely visible.
The coil identification labels are FL36A-4 2011 09A
Hi Roy
We do not know the correct reading for that particular coil so cannot help you determine if 1.8Kohms is good or bad.
I have two victa 18s early 50s models and ive tested both coils at 20kohms and i get a reading of 6.86 and 6.66 are these coils good can you tell me please…john…
Hi John
We do not have a new coil to compare to but from previous testing of the older generation coils a measurement of around 6k ohms is normal
Thank you for the videos of how to test a coil and a spark plug, very well explained and informative.
I have a Victa Mustang which was given to me by the owner who said it will not start. I tested the spark plug by pulling the starter cord with the sparky out of the mower. There was no spark. I tested the spark plug (as per your video with a multimeter) and it was in the range you specified. I took off the cover and then tested the coil. Again within your tolerances. However I noticed there was a very heavy build up of oil and dirt on the coil and the flywheel. I cleaned this deposit off and cleaned the side of the flywheel with a scotch pad. I noticed after the clean there seemed to be two “patches” which could have been copper I’m not sure, on the side of the flywheel. Do these patches have anything to do with the coil generating current? I tested the sparky out of the motor with the stop switch wire disconnected, no spark.
I’m at a bit of a loss where to go from here.
The test are most likely indicating a fault with your ignition coil or ignition module as you cannot get a spark. Some ignition modules are integrated into the coil and some are separate. If yours is separate it will be located underneath the black plastic carburetor it is a smalls silver module. The only way to troubleshoot further is to begin replacing components you believe to be faulty. In the case of a combined module and coil there is only 1 component to be replaced if they are separate it could be 1 of the 2 components that is faulty. The patches you describe are the magnets in the flywheel these do not wear out and do not need to be replaced.
I have same problem as Kerry. I have no spark ,the coil is indicating resistance within the range , yet I cannot get any spark. The engine is out and I’m turning it with a drill to get enough rpm, and the kill switch wires are disconnected. Local shop tested the magneto and confirmed that it’s good as well.It’s a unit without a module. I cannot understand what else could be causing this.
Hi Danny
Have you replaced the external ignition module below the carburetor? Also is the module still attached to the engine it needs to be grounded to the engine to function correctly.
Hi, no there is no module on this model it’s 1991 electronic ignition so when I dismantled it all I found was two wires to the carburetor and a third that is earthed to the chassis.
Hi Danny
Okay In your case the module is integrated inside the coil. If you have confirmed your spark plug is good and the magneto gap is okay then the only reason for no spark would be a fault with the coil.
That’s what I’ve been thinking. Are you guys able source them?
Unfortunately our suppliers have stopped making them and we have not been able to find anyone else that produces them.
Hi again, and thanks for the parts I got, sadly I had to obtain the coil elsewhere, but did get one and did install. Now I am miffed.
Testing for spark using a drill with a socket I found the spark is weak and only at high rpm turning the correct way. Turning the engine in the opposite direction (clockwise from underneath) I am getting a very good spark at any RPM. The coil is installed correctly, I have checked several times.
Any ideas please?
Hi Danny
We have never tested the spark in reverse So cannot comment on whether that is normal behavior. All We can suggest is to find a working mower to compare to and swap over one part at a time until you determine the exact part causing the fault
Looking for a coil ma05678a but can’t find one anywhere you wouldn’t know if there is an alternative coil or where to source one by any chance
Hi Mate
We have no way to source these older coils and do not currently know an alternative.
Hi, mines measuring at 14.23 ohms. I guess it needs replacing. How do I buy an ignition coil from you?
Thanks.
If you coil has a molded square part inside it 14.23 is ok, Such as Coil MA05599A. If your coil does not have the molded square part then it should have a seperate ignition module under the carburetor and 14.23 would be a high reading. The coils are no longer available so we are unable to supply them.