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Tips
Tips

no fire from my coil?

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starts with -.280 and then jumps, -.140, -.067, -.048, -.020, -.09 down until hits 0. The numbers down vary
 
Great!. Now reverse the meter leads. Then take the meter lead over to the long spring contact [the one that moves] on the points and repeat this last test! Tell me what it do. /ubbthreads/images/graemlins/grin.gif--Keoke
 
I put the red lead to the dizzy wire and the black to the points, part that moves, and it does the same -.280 down to
-0.00. Did I connect the leads right?

I also put the red to the points and the black to ground and did the same as above
 
Yep its OK, one more test en I'm going to bed. /ubbthreads/images/graemlins/grin.gif Set the meter on the 200 scale, remove the card from the points make sure the points are closed. Now make a resistance measurement [[from the diconnected end of the coil lead going to the dizzy]] to ground. Tell me what you see.--Keoke
XXXXXXXXXX /ubbthreads/images/graemlins/savewave.gif /ubbthreads/images/graemlins/savewave.gif
Note this is just like the jump test we just did except the points are now closed and we are using a lower resistance scale.
 
with the red lead on the + side of the coil, points closed, and the black to ground and the meter set to 200 it jumps from -30.0 down to 0
 
Yes, but I also want to see the results of the low resistance test.--Keoke
 
Yeah it was about as clear as mud /ubbthreads/images/graemlins/grin.gif Diconnect the lead from the coil that goes to the dizzy. Remove the card from the points. Set the meter on the 200 scale. Ground one end of the meter. The other meter lead will now be connected to the wire that goes to the dizzy.Tell me what you see--Keoke
 
points closed, negative wire on the coil disconnected (goes to dizzy and tach), red lead inserted into the lead that plugs into the negative side of the coil, meter set to 200, black wire on ground meter stops at 4.0
 
Replace: Points, Condenser and rotor. Get two rotors and two capacitors if you order from the usual suspects as their quality has been very poor. Before installing the new rotor remove the small metal plate on the inside. Your coil is OK. Note!! do not use any of the existing components as spares you will be left on the side of the road. Thanks for your Patience --Regards Keoke.
 
I ordered them today on a hunch...how did you determine they are bad?

I thank you for your time and patience - next time I'm in LA I will buy you a beverage of your choice
 
The low resistance test was way too high [Points], The Jump tests on the Capacitor indicated the ability to charge/discharge but not in a linear mode and it's performance under voltage stress can not be assured. The spark test verified the coils condition. The notorious poor performance of these rotors just got it thrown in.---Keoke- /ubbthreads/images/graemlins/cowboy.gif
 
Keoke, please explain either here or by PM how the readings (jump test?) indicate the condenser is suspect. I'm not questioning you, I just want to understand what you had Greg measure.
 
Oh DK just dig out a old capacitor from your junk box. apply the leads from an Ohm meter set to its highest scale between its contact lead and the case. The Capacitor initially is a virtual short circuit and the initial charge current will make the meter go {jump} to a high scale and then drop off to zero as it charges and the charge current goes to zero. Reverse the leads and it should discharge through the out put impedance of the meter in the same fashion. Using a low ohm scale you should see a lesser current rise and then return to zero. However, if it fails to go to zero but stops at a readable resistance say 4-to-5 ohms or more it is suspect.---Keoke
 
Thanks Keoke. I'll keep that in mind for future troubleshooting.
 
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