Points resistance

How do you check points resistance with a multi meter and what should the readings be? This is the third set of points I've put in my Jubilee It runs great for a couple of weeks then crap. I'm thinking about putting in electronic ignition, how hard are they to install?
 
(quoted from post at 09:29:14 09/29/17) How do you check points resistance with a multi meter and what should the readings be? This is the third set of points I've put in my Jubilee It runs great for a couple of weeks then crap. I'm thinking about putting in electronic ignition, how hard are they to install?
oints are just a switch. Set your Ohmmeter to lowest scale, press the two leads very firmly together & note the reading (should be very near zero). Remove distributor cap, rotate engine until points rubbing block is on a flat of cam (you should see points contacts firmly closed and see air gap between rubbing block and cam flat). Now place one meter probe firmly on the grounded side of points and other probe on non-grounded side and take a reading. It should be, as before, near zero Ohms.
 
Bob I've come to think that's the normal life of points you buy now days. When you do as jmor suggest's try to avoid moveing or compressing contacts by touching probes to distributor plate and where condenser wire connect's to points and distributor wire.
 
Are the points closing in gap, getting burnt of forming deposit?

That will help in diagnostics, points should last years.
 
Do yourself a favor and put in a Pertronix electronic ignition. Best thing I ever did for my 841. Easy install and since they work with a point style coil, so you can still use points as a back up.
 
I would suggest measuring voltage rather than resistance. With the ignition on and points closed, there should be zero volts across the points. I'd replace the points if you see more than half a volt, and I'd expect it to be much less.

There is a reason you're burning up points. I suggest you try to figure out what it is. Has the tractor been converted to 12 volts? If so, there needs to either be a resistor in series with the coil, or the coil should be replaced with one intended for 12 volts with no resistor. Another possible cause is contamination from oil or grease; the distributor cam lobes should have only a minimal amount of lubricant; otherwise it will sling off and contaminate the points.

It seems to me as many people have trouble with the Pertronix units as are happy. There's no reason why your original ignition shouldn't do the job just fine.
 
That is a very good point, no pun intended, by applying current across the points, bad points should develop a voltage.
 

If points would last for years that would be great. I have been messing with engines of all types since before electronic ignitions were invented and it seems to me points have always been a major culprit in ignition based problems.
 
Check all you wiring connections. Also make sure your battery ground connection is good. Are you replacing the condenser also? Is this 6 volts or converted to 12 volts? + or - ground? If - ground, be sure your points connect to the - terminal on the coil. If + ground, then to the + terminal. Have you always had this problem or is this something new? I did just change to Pertronix ignition just because of the high humidity here in Florida. Points should last a few years though if everything is correct. When I was a young fella, everything was points so I know that they work. I just don't work as well as I used to.
 
(quoted from post at 10:04:31 09/30/17) If your points are burning up that quick I would suspect a bad condenser.

Or a china set of points...

On china points, I would have to pull the cap, run a piece of paper through the points, to clean off the corrosion/dirt/whatever, and then the engine would start fine. This would have to be one a least once a week or more often.

Replacing them with a quality set of points and I dont have to touch them for years, 10 years or more.
 

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