12 V square coil

I have been working on a customer's early 8N which he regularly beats the H--- out of. He is a 50 YO special needs adult who unwittingly abuses everything.

It wouldn't start, so he kept cranking on the starter until the insulation on the + batt cable melted off. And probably left the key "on" until the batt was totally dead. So I replaced the points and condenser as they were about 2 years old and points were a bit sticky. I got very weak spark with new points and cond. I ohmed out the old coil, primary seemed good at about 1 ohm, but I did not know what the secondary coil resistance should be, but it was many Kilo ohms. I ordered a 12 volt coil from one of our site members and installed it this afternoon. It had a sticker "12 V". My question is should I be running the ignition wire direct to this coil, or should I be running the primary coil power through a ceramic resistor block (like most 12 V auto ignitions did)? I believe this new 12V coil is sourced from Tisco.

Thanks for your replys.

Paul in MN

PS. He also seems to have burned up the starter motor which was also about 2 years old. I replaced that one with a Denso type gear reduction starter that engages the ring gear from the engine side. I maintained the safety start (tranny) switch with a relay circuit.

Square coil should have the original wire wound ballast resistor.
The one mounted on the back of the dash. 6V or 12V.
If it's a 12V coil it doesn't need any other resistor.
If a 6V coil, it may need an additional ceramic resistor.

Royce,

Thank You!

Paul in MN

Wiring/electrical is all cobbled up no doubt -go to the other Ford N-Tractor site and download "WIRING PICTOGRAMS by JMOR". Stop buying and replacing parts without knowing if good or bad. Also, stop assuming/guessing at the problem, 'probably' and 'seems to have' and 'believe it is' statements are pure opinion, not fact based. 12V Coil? Is the tractor a 12V/NEG GRN system using an alternator? If so, is there a voltage regulator still in the circuit? There shouldn't be if 12V/NEG GRN and an alternator installed. If old coil measured 1 OHM static, pigtail to top post terminal, that is about right for a 6V coil. 1.3 - 1.5 OHM is what it should be, but, does not the mean coil is good. Don't assume because a sticker says 6V or 12V it is right -always check first. You are also assuming the starter is 'burned up' too -that is an opinion, not based on fact -did you motor test it? "...so I replaced points and condenser..." -again why? Points and condensers will last 5-7 years easily. Starters and generators will last twice that long easily. All these statements based on normal usage under correct wiring circumstances. Your 'special needs' fried may just need to be properly instructed on how to treat things like his tractor.

Tim Daley(MI)

Tim,

I appreciate your reply with the advice about not changing parts unnecessarily. I have been servicing this tractor for nearly 30 years. Yes, I have changed some of the wiring, but it is far from being cobbled up. It has a Delco SI 10 alternator, eliminated original regulator, new wiring harness some time ago. The owner is not permitted to drive a car, but is allowed to drive this tractor, so it gets a few thousand miles every year. Thus it has 12 V lights, flashers, trailer light wiring connection. It has had 8 starter motors replaced by me, and is on its 3rd ring gear. When he runs out of gas, he cranks on it until something burns out or the battery dies. It has started on fire (gasoline, burning up the electrical system), replaced a few clutches as he has dropped the clutch pedal and busted the center out of the clutches, and broken off rear wheel studs when dropping the clutch. When he has been frustrated he has taken a hammer and beat on the starter or sheet metal. This guy is very strong and has even broken off the throttle lever a few times. It is a testament to how well built the 8N is, that this highly abused machine has lasted 71 years, and can still be fixed with the lesser quality parts we get from Asia or India.

Why do I continue to fix it??? I often wonder! But wife and I have a special needs daughter and have a soft spot for helping out others. His Dad (good guy with lots of patience) was killed by another driver losing control on icy road about 28 years ago, so his family adopted me for the mechanical chores with the tractor that was his father's and grand father's. He now has his sister's 8N as back up for when this one is out of commission. It sees the same level of abuse, so I do what I can to keep it running as well. I have converted that one to 12V w/alternator and lights and flashers also.

His mother has suggested buying a new small JD, with warrantee, but with plastic hoods and other plastic parts, it would be junk in less than 2 years. The 8N is close to bullet proof for this application, so I keep fixing them both.

I bought my first 8N in 1970, OH'ed in 1974, and it is in very good mechanical and electrical condition. So I've had a lot of years of learning to fix the 8N's.

Good Day to You!

Paul in MN