640 Just Died

While idling, my 640 quit running.
No spark at the plugs, no spark at the coil output.
Got 12 volts up to the battery side of the coil.
This is a 12 volt conversion using a resistor and resistor coil.
Coil or condenser, and are these parts including points available at a parts house? Nearest parts are 32 miles, nearest tractor place is 52 miles.

Any help would would be appreciated.
 
If your points are not opening and closing you will not get spark out of the coil. Maybe the screw holding the points has loosened or the rubbing block on the points has worn down. Maybe grease or dirt has gotten on the contact surface of the points. It could also be a dead condensor.
Any auto parts store in a rural area should have the points and condensor.
If you have a coil marked "12V No External Resistor Required" you do not need an in-line resistor.
Since you are so far from a parts store you might as well go ahead and get new points, condensor and a true 12V coil with the internal resistor.
 
Points are opening and closing, no spark there either and points look almost brand new.

Coil is marked external resistor, guess it's time to get rid of it.

Any suggestions on a replacement numbers etc.?

Guess I'll bite the bullet and hit the auto parts store in the am.

Thanks.
 

OK, now I'm thinking (and it hurts), this is a 12 volt conversion I didn't do, so when I make the long drive for parts what do I ask for in the way of points and condenser?

Keep in mind there is a resistor in the system (I wouldn't mind getting rid of it) so does that mean they are "standard" points and condenser?
 
Get the points so they are sitting closed. Now with the key on try opening and closing them. Do you have a spark there?? If you do not then try taking a screw driver and lay it across the points. Do you get a spark then?? If you do then the points need cleaned if you do not then you have a short some place. If as I said you do not get spark like I said then take the wire off the coil distributor side. and with the key on set the wire on and off the coil. If you get spark then you have a short between the distributor and the coil and need to find it and maybe a very simple fix.
 
Here's the number for the proper 12 volt coil.
NAPA Part No. IC-14SB. You can then get rid of the in line resistor. The points and condenser should be okay unless the condenser is toast too. Hope this helps.
 
(quoted from post at 04:30:04 07/20/09) Here's the number for the proper 12 volt coil.
NAPA Part No. IC-14SB. You can then get rid of the in line resistor. The points and condenser should be okay unless the condenser is toast too. Hope this helps.

Again, are the points and condenser "standard".

There was no spark across the points when I opened and closed them.
 
The 12V conversion has nothing to do with the points and condensor. Just buy the standard parts for a 640.
 
IIRC your ranch is near Leakey. Do you drive to Uvalde for parts? Are you in Extreme or Severe Drought coditions? Here in Lampasas we're in Extremely Severe Drought.
 
Points run hot,oxides form that insulate them.Clean the points.Your ammeter should flip to 4 amps discharge when cranking,easy fix.
 
You should be able to get the points and condenser at any decent auto parts store, although you'll frequently get a blank stare if you ask a counter man to look up a part for a tractor. I think, but I'm not certain, that there is an automotive application for these points.

If you have access to a voltmeter, check the voltage on the distributor side of the coil primary windings. It should switch between 12 and zero volts as you manually open and close the points.
 
(quoted from post at 07:57:48 07/20/09) IIRC your ranch is near Leakey. Do you drive to Uvalde for parts? Are you in Extreme or Severe Drought coditions? Here in Lampasas we're in Extremely Severe Drought.

My place is in Utopia, about 22 miles from Leakey.
We are under severe drought conditions here. Got 1/2" rain Friday evening, 1/2 later you couldn't even tell it rained.

It's bad enough that I have 5 bucks coming down for water twice a day just for the water.

Parts, that's crap shoot. Sometimes it's Sabinal (32 miles one way), sometimes Bandera (32 miles one way) Leakey (22 miles one way) and Uvalde (50+ one way). I try to plan trips to coincide with Wal Mart or other services.

Country living.
 

OK, got all the parts, and before I screw up what is the polarity on the new coil. Old one had battery on one post, this just has +/-.
 
Found the info I needed on the coil - went to dist., put it in.........no start.
OK, I'm really electricly challenged (spell to), so here we go again. No fire from coil wire. Removed it and looked at it again. Didn't see anything wrong, started put it back, then decided to cut the ends off and fold the wire over and recap it. Pulled the first end off, wire came out off wire, but was non exsistant under the brass cap. Stripped it put the cap back on.......now I have to go back to work this afternoon.

At least I have all new ignition parts.

Why is it always the last thing I check with electric stuff (batteries included) turns out to be the problem.

Thanks everyone for the help.
 
(quoted from post at 23:08:01 07/20/09) Maybe that black cloud over your head will bring some rain. :)

I hope so, we need it bad.
We are in a severe drought area, the Sabinal River has quit running in most places.
Got 1/2" last Friday, good for rinsing the dust off the trees.
And speaking of trees I was using a boom to move tree parts when it quit.
Been loosing a lot of old Spanish Oaks lately. Had another 2-1/2' one last night. They are not noted for long life like other oaks.
Bright side, more BBQ wood.
 
You must have a 6V coil if you need resisitors on that installation.

Have you checked the points? Are the buned, pitted, corroded or poorly adjusted? Using a volt meter on the distributor side of the coil, crank the engine with the ignition on and see if the voltage alternates from 12v to near zero as the points open and close. If it does the points are opening and closing and the coil has continuity.
There is no easy check for a condensor that I know of so you can replace it and see if that corrects the problem.
Did you check for continuity across the coil primary? If you don't have that your coil is bad. I would suggest that if you replace the coil, buy a real 12V coil (like NAPA IC-14SB ~$15) which has the correct resistance for a 12V system built in and get rid of the resistors.
 
(quoted from post at 23:08:01 07/20/09) Maybe that black cloud over your head will bring some rain. :)

Another little black cloud.........the display on my multimeter just gave it up, all it shows is little "sticks" in a couple of places.

Tomorrow is another day.
 
(quoted from post at 03:12:28 07/21/09) Broken display could be a weak battery.

Put a new battery in, same results.

Got 4 Harbor Freight backups ($2.99 each) at home, just have to bring one up here next trip.

Black cloud is working, getting some rain right now.
What we need is a "friendly flood". Need to get water flowing in the rivers and flush them out.
 
(quoted from post at 17:20:24 07/20/09)
(quoted from post at 03:12:28 07/21/09) Broken display could be a weak battery.

Put a new battery in, same results.

Got 4 Harbor Freight backups ($2.99 each) at home, just have to bring one up here next trip.

Black cloud is working, getting some rain right now.
What we need is a "friendly flood". Need to get water flowing in the rivers and flush them out.
Sounds like your meter's toast. How bout sending some of that cloud over here. We only had 1/2 inch in june and got another 1/2" last week, but still dry as a powder house.
 
Are you saying that the problem was nothing more than a broken wire between the center of the coil and the center of the distributor cap?
 

Yes, that's what I'm saying.

After looking at it twice and checking continuity I thought it was OK.....that's what I get for thinking.

One would think the "juice" would flow through the end, but it looks like it won't.

Been accused of a lot of things, but being smart hasn't been one of them, especially when it 's electricity.

Again guys thanks for all the help.

Case closed, time to move on.
 
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