magneto problems

   / magneto problems #11  
Eric_Phillips said:
I checked the points and when open the cutoff post has no continuity to ground so they do break. I checked the gap and it seemed a little tight so I recapped them. I then hooked everything back up and tested the cutoff post and sure enough there was continuity to ground again. I disconnected the coil and the wire to the points and the ground wire is shorted, no resistance. From the spark plug terminal to either the ground or points wire is open, no continuity at all. It is a Zico X5700B coil. Am I correct that this is a bad coil?
Click to expand...

Disconnect the wire connected to the outside terminal, keep the lose end away from the terminal. Crank your machine over now and see if there is spark, or if you go the route to start the engine and she fires up you can stop the engine by grounding that terminal with a screw driver.

Testing your coil maybe a futile effort unless your sure which coil is being tested, inside the main coil there are primary and secondary coils, the latter coil produces the high voltage spark supplied to the spark plug.

Some magnetos came equipped with a kill button, shown below.

kill.png
 
   / magneto problems #12  
Your coil obviously looks much different than the one shown in the youtube video but the procedure for testing is the same.

 
   / magneto problems #13  
Magneto coils will share a common ground.
One side will read low resistance while the output will be very high, the high is the one that goes to the plug.
Points switch the low side.
In that magneto coils are 'potted' I suggest that rarely do they go bad.
The main usual problem will be the capacitor or possibly badly pitted or glazed points.
As a remedy the points can be 'dressed' (fine emery or a file) but that is not really permanent. (dressing damages the fine polished hardened surface)
The usual recommendation is to replace points and condenser as a pair.
Point gap is somewhat critical as over or under changes the timing.

My 2 cents, hope I help a bit.
 
   / magneto problems
  • Thread Starter
#14  
rustydollar said:
Your coil obviously looks much different than the one shown in the youtube video but the procedure for testing is the same.

Click to expand...

The first coil he tests looks to be the same coil I have. When I test the primary I get no reading so it looks like the primary is open. When I check the secondary I get 0 ohms like it is shorted. Being $60 for a new coil I just wanted to make sure it was the coil and not something else.

Wouldn't burnt or corroded points show some resistance when closed?
 
   / magneto problems
  • Thread Starter
#16  
I used an analog meter to test the coil and I checked the accuracy of my digital meter. My meter on only measures 0-2000 ohms with an accuracy of 1.5% + 2 Ohms. So trying to read about 1.2 Ohms and 9000 Ohms won't work. So the analog tester I used said 1 Ohm across the primary and 12000 across the secondary. From what I can dig up this coil is supposed to be 1.2 and 9000. I think this coil is good. My screw driver stuck to the magnets so they are not dead. I guess I start with the cheap stuff and try new points and condenser.
 
   / magneto problems
  • Thread Starter
#18  
I put it all back together to give it one more try. Sure enough now I have spark. Not sure what the problem was but now I am back to fuel issues.
 
   / magneto problems #19  
   / magneto problems
  • Thread Starter
#20  
DJ, thanks for the links but I already had the manuals from that site. I cleaned up the carb and it is now running again. Thanks for everyones help.
 
You must log in or register to reply here.
 

Footer Links 1

Top