Another 8n wont fire question. Long post

[TommyNC]

Hi. I've been lurking here on and off for a while. I have pretty much resolve most of my problems from this board and others. Now I'm stumped. 52 8N side mount dist. Over the last couple of months I have been refurbishing this tractor. I had it running like a sewing machine. New starter, rebuilt generator, etc, etc. Then I took it apart and painted it. (I took photos for future reference) Back together now, no fire from the coil. Over the last 3 weeks, I have changed the coil. The points and condenser 3 times, triple checked all my photos of prior disassembly, positive I put it all back the way I had it when it was running. Now. I've got 6 volts on the high side of the coil. 6v going in the dist. Doubled checked that the distributor is grounded. No spark. Bypassed ignition, no spark. bypassed ignition and ballast, no spark. Hot wired the coil, no spark. Put in a new napa coil with built in resistor and eliminated ballast resistor. Didn't fix it. One thing I noticed this evening is the test light on the distributor side of the coil is not going off when the points close. Thinking the condenser, I changed them again. Didn't help. My first suspect was a grounding problem. Not so sure now. My brain has just about lost its spark from this thing. I'm throwing in the towel. Someone please tell me what I missed. Thanks

 

[pmsmechanic]

Just a thought. Make sure the points are making a connection when they close.

 

[deerseeker001]

Welcome from Wisconsin

 

[Soundguy]

your post is frought with problems.

1, 6v side mount 8n DO NOT use ballast resistors.

2, NAPA coils DO NOT have resistors in them. they are voltage specific to application.. whether 6, 8 or 12v.

using a 12v coil on a 6v machine or using a ballast resistor and 6v coil on a side mount will CAUSE no spark.

now.. the real issue.

you said your test lamp is not going off when the points close...

that means you are saying the lamp is on when the poitns are open.

that means the points .. while open.. are SHORTED!

spark happens when points OPEN.. not when they close!

prime location for a shorted set of points is the wire and insulator at the side of the distribuitor.. many times the insulator cracks and that wire touches the side of the dizzy, also, from there is a copepr strip from that bushing over to the points. if it touces the dizzy side.. it shorts the points.

here's a test..key off.. no hotwireing.

run a test lamp from bat hot to input side primary of coil. output of primary to the dizzy .. roll engine over. lamps should BLINK. it should be off when points open, and on when closed.

if it never comes on.. primary is open.. or points not closing / other bad connection.

if lamp never goes off.. something is shorted fromt he priamry of the coil to the points. like the two items i mentioned.

now go troubleshoot correctly and find that problem instead of continously buying the same sets of parts over and over and over.

ps. loose the INCORRECT parts. you want a 6v coil.. and NO ballast ressitors for a side mount 6v 8n.

 

[TommyNC]

Ok. Thanks for the responses. I know for a fact the points are closing. So, from what I'm reading here, it has to be a short. Apparently, the previous owner, added the ballast resistor. So, I'm going back to square one. The initial coil that was on the tractor was reading around 1.6 ohms which I think is acceptable for a 6v coil. Its not labeled. I think its a 6v. (it was running with that coil) I'll reinstall it. The napa coil is a ICI4sb. It states it has a internal resistor. I'll use it on something else. I'm going to leave off the ballast resistor. I'll run some test in the morning and see if I can get it going. I'll report back. Thanks!!

 

[Soundguy]

the napa coil does not state it has an internal resistor. it states that no external serial resistance is needed .. an ic14sb coil is a native 12v coil. primary resistance falls int he 3-3.25 range usually.

your 1.6 ohm coil and NO resistor is what i would use.

PS. visually observing points close means nothing...

I have seen points with a film on them that mechanically closed.. but did not make electrical connection.

in any case. closing is not your issue. .. with the data you reported. the circuit is 'short' before it gets to the points...

Ok. Thanks for the responses. I know for a fact the points are closing. So, from what I'm reading here, it has to be a short. Apparently, the previous owner, added the ballast resistor. So, I'm going back to square one. The initial coil that was on the tractor was reading around 1.6 ohms which I think is acceptable for a 6v coil. Its not labeled. I think its a 6v. (it was running with that coil) I'll reinstall it. The napa coil is a ICI4sb. It states it has a internal resistor. I'll use it on something else. I'm going to leave off the ballast resistor. I'll run some test in the morning and see if I can get it going. I'll report back. Thanks!!

 

[Soundguy]

and here's the proof on that napa ic14sb

pic quality is poor.. but you can read exactly what it says!







i wish that 'internal resitor' rumor would quit being propogated and go away!

 

[TommyNC]

" I wish that 'internal resitor' rumor would quit being propogated and go away!" ....Dang..I got sucked up in that vortex on the stovebolt forum. I stand corrected. That is the coil I have.. I'm throwing in the towel on this too!!!! Ha!

 

[Soundguy]

did you find the short?

 

[Soundguy]

" I wish that 'internal resitor' rumor would quit being propogated and go away!" ....Dang..I got sucked up in that vortex on the stovebolt forum. I stand corrected. That is the coil I have.. I'm throwing in the towel on this too!!!! Ha!

sorry.. not trying to be abrasive or anything.. .. I've worked on literally hundreds of old tractors ( even own a few myself ) and I just get a lil nervous eye twitch when i here someone telling someone about their internal resistor coil... all those years of engineering school probably don't help the situation either.