John deere 520

[JD630]

We have been having trouble with our JD 520. It keeps taking points and once in a while condensers out. I rebuilt it last year and it ran fine until fall come, it started back firing, and points woulds only last a week. Now when we set the points the key is off and when we turn the engine over there is a small blue spark that occures. I thought there wasn't suppose to be power when key is off. Also it will run uneven with the generator hooked up to charge the battery. It is our everyday user and would be nice to have it working with out fighting it. Any ideas? Thanks

 

[buickanddeere]

Using a 12v or a 6V coil? Coil and battery polarity is plus or neg? Sparks once or every time? Does the battery run down when the tracror is sitting? Is the wiring 100% factory or has somebody been tinkering?

 

[JD630]

Using a 12V coil on a 12V system, with the neg polarity(positive is ground) and it has factory wiring. The battery doesn't run down when sitting. It sparks every time in the distributor with the key off.

 

[buickanddeere]

Supposed to be a 6V coil.

 

[JD630]

Why is it suppose to have a 6V coil.

 

[buickanddeere]

The 520 has bypass starting.

 

[JD630]

So by switching it to a 6V coil should stop the little blue spark/problems that we are having. Or could it be in the wiring? What does the starting system bypass that would make it have to have a 6V coil.

 

[buickanddeere]

There is more than one problem. The coil is supposed to be supplied full electrical system voltage while cranking via the bypass on the starter switch .once running the 6V coil is supplied 6V via the ballast resistor run circuit.
The condenser/capacitor will store a charge .
Somebody has either tinkered with the wiring and/or something electrical has failed. Is the generator regulator properly wired and set?

 

[JD630]

Ok that makes sense. I believe the generator is wired properly. but I dont know it is set. Before all of this happened the generator kept the battery fully charged, and we never had a issue with it.

 

[buckshot721]

Get a coil with a ballast resistor in it. Had a 57 Chevy that would eat a set of points for lunch, got an Accel Super coil (12 volts with ballast) no problems since, starts and runs better also. Also used the Super coils on a couple of tractors also.

 

[buickanddeere]

Buck. There has not been a coil with an internal ballast since the 1930's. We keep telling you guys that but you refuse to beleieve it.
Why go with a 3.0 ohm 12V coil and loose the advantage of bypass starting?
I'm not getting a clear understanding of where this sparking is.

 

[JD630]

With the ignition key off, and while setting the points, a blue spark will occur between the points when the tractor is turned over to verify the gap.

 

[buickanddeere]

A blue spark between the point's contacts on every opening and closing or just the first ?
Have you used a volt meter to find voltage on coil side of the points or the ignition side of the coil when the main switch is off?

 

[JD630]

there is a blue spark everytime between the contacts, and I forgot my multi-meter at college but i haven't tested any voltage.

 

[buickanddeere]

Find out why there is still power to the coil with the switch off. Go through the wiring harness point by point with the wiring diagram. Something somewhere is shorted or mis-wired.

 

[JD630]

Where can I find a wiring diagram for a 530, I dont have one in my books that I have.

 

[beenthere]

I'd try my Deere dealer and hope they could bring one up on their computer or in their "files", then get a copy of it.

 

[rScotty]

Hello JD630, did you ever get this worked out with the 520? We've still got an old 530 that was our everyday user for many years. Never had much problem with it and most everything is original. It's not a rebuilt tractor....just an old original and probably similar or the same electricals as the 520. So many hours on it that I'm on the second tach/hourmeter. The bushings wore out on the original tach, but the rest of the tractor is fine. I've got JD books and such plus some electrical knowledge.
luck, rScotty

 

[JD630]

Hey rScotty, I haven't figured it out yet, but we did put a new coil on the 520, we got it from a dealer online and it is called flame thrower. But I just leave the generator unhooked, and I haven't charged the battery since january, or even look at the points and its been running everyday for about a hour. But one day I did hook up the generator and the tractor ran good for a few minuets but seemed to start missing.
Any Ideas,
Thanks