Magneto trouble
Posted: Tue May 23, 2017 5:18 pm
Hi all,
I have been experiencing trouble with my Lucas RF4 magneto on my E27n. It is a previously reconditioned magneto so all intervals are good. It gives off a spark but does not fire the engine. I tried a mates identical magneto on and the tractor started up first rev, so definitely a fault with my magneto.
I am interested in looking at it myself, and currently have it in bits. All internals are pristine as I know it is a previously reconditioned magneto. My thought is that the spark is too weak as it fires outside but not under compression, therefore I have resistance checked the primary and secondary coil windings. The primary coil has negligible resistance, which is good. However the secondary coil has a resistance of 4.6 ohms. I am pretty sure this figure is too low as generally secondary coils have an extremely high resistance (thousands of ohms) in order to step up the voltage.
I am therefore asking if anyone has any experience testing coils or what their houghts are here? Or if anyone knows or is able to test what a working magneto secondary coil resistance should be?
I have been experiencing trouble with my Lucas RF4 magneto on my E27n. It is a previously reconditioned magneto so all intervals are good. It gives off a spark but does not fire the engine. I tried a mates identical magneto on and the tractor started up first rev, so definitely a fault with my magneto.
I am interested in looking at it myself, and currently have it in bits. All internals are pristine as I know it is a previously reconditioned magneto. My thought is that the spark is too weak as it fires outside but not under compression, therefore I have resistance checked the primary and secondary coil windings. The primary coil has negligible resistance, which is good. However the secondary coil has a resistance of 4.6 ohms. I am pretty sure this figure is too low as generally secondary coils have an extremely high resistance (thousands of ohms) in order to step up the voltage.
I am therefore asking if anyone has any experience testing coils or what their houghts are here? Or if anyone knows or is able to test what a working magneto secondary coil resistance should be?