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Discussion Starter #1
So first post and looking for some help.

tractor is going thru condensers faster than I can replace them. I always replace the points and condenser as a pair. Coil checks 1.8 ohm across the poles and has a resistor in line on the power wire. Points set at .025-.026.

So had a set in it that ran for 2ish years no issues. I only put 40-50 hrs a year on this unit. Decided to tune up before hay season, I hay about 20 ac. Bought the points and condenser from the local tractor dealer/parts house. Ran less than 2hrs before it started acting up. Replaced both and ran just over 2hrs before failing.

I am planning to convert to petronix which I have on order but need this thing to run today.

HELP

Thanks
 

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Are the contacts on the points burned, did the rub block wear down, is the distributor shaft bearing worn allowing the shaft to wobble, or has the rotor failed, or is the distributor cap cracked?

The other question is did you check coil impedance immediately after the tractor quit, while it was still hot? If the points and ignition components associated with the distributor test good, I would suspect the coil has moisture and when it gets hot it grounds the spark.
 

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Howdy Ike, welcome aboard the tractor forum.

Your coil primary resistance should be about ~1.6-2.0 ohms for a 6V coil, or ~ 3.2-4.0 ohms for a 12V coil.

The 1.8 ohms resistance (if your ohmmeter is correct) across the primary winding tells us that it is a 6 volt coil, and needs a resistor in series with the coil or it will burn the points. You say that you have a resistor in series with the coil. Measure the resistance of the resistor......should be about 1.6-2.0 ohms.

If everything checks out, I guess I would try a NAPA auto parts store to see if they can come up with better points & condenser.
 

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Discussion Starter #4
Are the contacts on the points burned, did the rub block wear down, is the distributor shaft bearing worn allowing the shaft to wobble, or has the rotor failed, or is the distributor cap cracked?

The other question is did you check coil impedance immediately after the tractor quit, while it was still hot? If the points and ignition components associated with the distributor test good, I would suspect the coil has moisture and when it gets hot it grounds the spark.
The points actually looked ok, rub block was fine, rotor and cap are like new. The shaft does have a tiny amount of play but not more than .001-.002. If the bearings were the issue I'd expect it to be more consistent as well.

I did not check the coil as soon as it started acting up however since I need to use it today I'll check it when hot. I really don't expect the coil as it's near new as well and hasn't seen a drop of rain or water in years.

thanks
Ike
 

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If the coil tests good when hot, check the condenser. Unbelievable, but a third of them are showing up defective right out of the box. Thank you Global Trade and underpaid workers!
 

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Discussion Starter #6
so did manage to limp thru the last of hay season so now we have time to fix this thing.

To make things easier I hooked the condenser t

Checked the coil hot and the resistance had gone up considerably to the 2.2-2.4 range. Meter was fluctuating. Then I checked the resistor and it had dropped considerably to about 1.4-1.6. It had been checking around 2.2 when cold.

So based on what I'm hearing from you guys, I'm thinking the resistor and probably the coil should be replaced (again) at this point.

Thanks
Ike
 
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